Dual Blade Mechanics

Dual Blade Mechanics

This will basically be an FAQ sort of thread with less Q and more A. Hopefully not a lot of F either.
The goal of this thread will be to objectively determine how the Dual Blade character class works. Not whether or not this class is broken or makes other characters obsolete.
Your input would be greatly appreciated as long as it is constructive towards this goal.

 Change Log

21/05/10

• Triple Stab information in Primary Mob Skills
  
• Updated some more Mirror Image
  
• Removed old Mirror Image information
  
• Added Triple Stab vs Bloody Storm end-game comparison
  
• Updated some mob skill information
  

15/05/10

• Damage Formula Bracket correction
  
• Mirror Image information
  

02/03/10

• Updated Mirror Image tables to reflect KMST 1.2.295
  
• Chains of Hell approximation
  
• Thorns
  

23/02/10

• Upper Stab + Mob Skill Information
  
• Mirror Image vs Upper Stab
  

22/02/10

• Skill Delays Updated to reflect KMST 1.2.293
  
• Triple Stab, Fatal Blow, Slash Storm, Bloody Storm, Tornado Spin tables updated to reflect KMST 1.2.293
  

First, I'll start off by clearing a very large misconception.

How do Blades work?

Blades are Blades. They are not Daggers. They are not Shields. They have their own attack. This attack is not added to their Dagger. Their Dagger attack is not added to their Blade.
A Dual Blade wields both a Dagger and a Blade. That's two weapons. When they use an attack, they will alternate with the weapon to deal damage. Half the attacks will be dealt with the Dagger, and the other half will be dealt with the Blade.
Blades have their own damage range.
Dual Blades are not broken because they have +x more weapon attack from their Blade.
When their character screen is displayed, the damage range shown uses a total attack from their Blade and Dagger. This is wrong. The damage range shown in their character screen is merely a visual error. They do not use this to deal damage, much like how an Aran can never hit the minimum range in their Polearm range.
It is most likely that any extra stats from a Blade do not affect the Dagger's range, and vice-versa. i.e. a Blade's +LUK most likely does not affect the Dagger's damage range, and a Dagger's +LUK most likely will not affect the Blade's damage Range.
More research into this area is required, but it is the most logical conclusion to assume that they are both completely independent of each other.

Calculating Damage
Claw/Dagger Formula:
Minimum Damage = [(3.6 * 0.9 * Mastery * LUK + STR + DEX) / 100] * WA
Maximum Damage = [(3.6 * LUK + STR + DEX) / 100] * WA
Dual Blade uses the same formula for Daggers and Blades. When calculating the range, do not add the Dagger's stats to the Blade's Range, and do not add the Blade's stats to the Dagger's Range.
Example character from Dusk's DPS chart:
117 Attack 7 LUK Dagger
65 Attack 7 LUK Blade
Total Stats without weapons: 33 Attack, 48 STR, 171 DEX, 1082 LUK

Displayed Ranged: 5052~8954
Dagger Range: 3504~6209
Blade Range: 2289~4056

The character display screen will show the Displayed Range. A Dual Blade will not be doing this much damage. Instead, a Dual Blade uses either their Dagger or Blade range depending on the hit of their skill; however, certain skills only hit once. These skills only use the Dagger Range, as far as we know. There may be exceptions.

Attack Speed Delays

Disclaimer: This chart does not account for any delays or 'cooldowns' between quick skill succession. At best, this char displays the minimum ~Normal (6) speed of all skills. For example, if Skill X has 600ms of delay, this at the least usually represents the amount of time before you are able to move after using the attack. At best, it represents the time before you can reuse the same attack.

 Spoiler

Attack	Time (ms)
tripleStab	870
flyingAssaulter	1380
tornadoDash	180
tornadoRush	960
tornadoDashStop	400
fatalBlow	1582
slashStorm1	600
slashStorm2	720
bloodyStorm	810
flashBang	510
owlDead	1410
upperStab	480
chainPull	660
chainAttack	1740
monsterBombPrepare	1200
monsterBombThrow	1200
suddenRaid	2700
finalCutPrepare	1200
finalCut	960

When observing Aran skill speeds, the skill delays proved to be a fairly accurate depiction of their actual speeds, outside of a single error with the Normal Attack's delay, which was part of Aran's combo attack mechanic, I believe. Thus, I believe we can use these as a basis for preliminary calculations. It would be, however, a great asset to have accurate readings of attack speeds for further precision.

Skills

When you attack a monster damage numbers appear in a certain order. They start at the bottom and rise upwards to display more numbers for attacks that hit more than once. As such, the bottom number of a multi-hit skill occurred first. This bottom number is a Dagger hit. The one above this hit is a Blade hit. The next is a Dagger hit, and so forth.

When calculating skill damage and DPS, it is required to separate the damage into its Blade and Dagger components first to determine the proper defense reduction and ratio of DPS that is applied from Dagger-only skills. For speed, the above chart can be used to compare Base DPS. The ratio is the same for every skill so unless you are comparing two different speed ranks, or two different classes, it is irrelevant. It is currently unknown how the Blade's speeds (Fast (3)) affect attack speed.

Triple Stab vs Fatal Blow

In this section, I would like to discuss the value of both skills as both are seemingly valuable in my opinion.

 Spoiler

 Triple Stab

Triple Stab - Prerequisite: 10 Double Stab (126%x2)
Triple Stab hits three times and also hits multiple monsters. As such, it hits two Dagger, and one Blade range. The Bottom and Top numbers are from the Dual Blade's Dagger range, and the Middle is from the Blade.
Triple Stab is a more unique skill for a Dual Blade as it always provides an imbalance from Dagger and Blade damage. The end result is 400% Dagger, and 200% Blade.
Points from Job I can be saved to be put into Triple Stab earlier. I personally recommend this, maxing, or at the least immediately reaching 3 mob hits on Triple Stab upon reaching Job II.
At level 1, it does 155% damage x3 to two monsters. Remember that two hits are Dagger, and one is Blade. Double Stab does 126%x2. Presumably, it does both hits with the Dagger; otherwise, un-equip your Blade if you're using Double Stab.
Double Stab has a special feature to it that improves its attack speed by two ranks, thus always 600ms.
420%/s with level 10 Double Stab, the prerequisite requirement for Triple Stab;
Triple Stab is 870ms Base. Most Daggers are Fast (4), thus 870 * 14/16 = 761ms.
407.3%/s Dagger + 203.7%/s Blade. Unless your Blade's attack is 6% of your Dagger, 1 Triple Stab is always an improvement to 10 Double Stab, as well as having the ability to hit multiple monsters, and having a larger range.

 Base DPS chart

Lv	Dagger	Blade	DPS	Mob DPS
1	356.32%/s	178.16%/s	22956.93	45913.85
2	367.82%/s	183.91%/s	23697.47	47394.94
3	379.31%/s	189.66%/s	24438.02	48876.03
4	390.80%/s	195.40%/s	25178.56	50357.13
5	402.30%/s	201.15%/s	25919.11	51838.22
6	413.79%/s	206.90%/s	26659.66	79978.97
7	425.29%/s	212.64%/s	27400.20	82200.60
8	436.78%/s	218.39%/s	28140.75	84422.24
9	448.28%/s	224.14%/s	28881.29	86643.88
10	459.77%/s	229.89%/s	29621.84	88865.52

 With Critical Ring

Lv	Dagger	Blade	DPS	Mob DPS
1	358.62%/s	179.31%/s	23105.03	46210.07
2	370.11%/s	185.06%/s	23845.58	47691.16
3	381.61%/s	190.80%/s	24586.13	49172.25
4	393.10%/s	196.55%/s	25326.67	50653.34
5	404.60%/s	202.30%/s	26067.22	52134.44
6	416.09%/s	208.05%/s	26807.76	80423.29
7	427.59%/s	213.79%/s	27548.31	82644.93
8	439.08%/s	219.54%/s	28288.86	84866.57
9	450.57%/s	225.29%/s	29029.40	87088.21
10	462.07%/s	231.03%/s	29769.95	89309.84

 Fatal Blow

Fatal Blow at level 1 does 82% damage in 5 hits. 3 of these will be Dagger, and 2 will be Blade.

 Starting with damage from the bottom up, it would be displayed like this:

[Dagger]
[Blade]
[Dagger]
[Blade]
[Dagger]

 Fatal Blow in Action

[video=youtube;bCvLEgmUW4o]http://www.youtube.com/watch?v=bCvLEgmUW4o[/video]

Fatal Blow's Base Speed is 1582ms. I do not know why there is a 2 there or why it is not evenly divisible by 30. As shown in the video above, this speed appears consistent with the speeds shown after being adjusted for Booster.
Level 1 Fatal Blow:
300% Dagger + 200% Blade
189.63%/s Dagger + 126.42%/s Blade
Clearly not able to approach Triple Stab's range, as a note.
Base DPS Chart

 Spoiler

Lv	Dagger	Blade	DPS
1	189.63%/s	126.42%/s	14222.98
2	199.12%/s	132.74%/s	14934.13
3	208.60%/s	139.06%/s	15645.27
4	218.08%/s	145.39%/s	16356.42
5	227.56%/s	151.71%/s	17067.57
6	237.04%/s	237.04%/s	19032.08
7	246.52%/s	246.52%/s	19793.36
8	256.01%/s	256.01%/s	20554.65
9	265.49%/s	265.49%/s	21315.93
10	274.97%/s	274.97%/s	22077.21
11	379.27%/s	284.45%/s	28947.30
12	386.85%/s	290.14%/s	29526.24
13	394.44%/s	295.83%/s	30105.19
14	404.55%/s	303.41%/s	30877.12
15	412.14%/s	309.10%/s	31456.06
16	419.72%/s	419.72%/s	33699.47
17	429.84%/s	429.84%/s	34511.50
18	437.42%/s	437.42%/s	35120.53
19	445.01%/s	445.01%/s	35729.56
20	455.12%/s	455.12%/s	36541.59

 With Critical Ring

Lv	Dagger	Blade	DPS
1	191.53%/s	127.69%/s	14365.21
2	201.01%/s	134.01%/s	15076.36
3	210.49%/s	140.33%/s	15787.50
4	219.97%/s	146.65%/s	16498.65
5	229.46%/s	152.97%/s	17209.80
6	238.94%/s	238.94%/s	19184.34
7	248.42%/s	248.42%/s	19945.62
8	257.90%/s	257.90%/s	20706.90
9	267.38%/s	267.38%/s	21468.19
10	276.86%/s	276.86%/s	22229.47
11	381.80%/s	286.35%/s	29140.28
12	389.38%/s	292.04%/s	29719.23
13	396.97%/s	297.72%/s	30298.17
14	407.08%/s	305.31%/s	31070.10
15	414.66%/s	311.00%/s	31649.05
16	422.25%/s	422.25%/s	33902.48
17	432.36%/s	432.36%/s	34714.51
18	439.95%/s	439.95%/s	35323.54
19	447.53%/s	447.53%/s	35932.57
20	457.65%/s	457.65%/s	36744.60

Taking a look at the DPS table, the Base DPS for maxed Fatal Blow is 455.12%/s for both Blade and Dagger.
Factoring an Adventurer Ring, this only improves to 457.65%/s.

Compare this to 459.77%/s Dagger + 229.89%/s Blade for Triple Stab (462.1%/s Dagger + 231.0%/s Blade with Critical Ring).
Despite having slightly lower Dagger DPS, Fatal Blow provides a significant improvement on the Blade DPS (nearly 2x more).
At level 13, we see Fatal Blow finally outdamaging Triple Stab's significant speed advantage.

However, Triple Stab still has the advantage of being a mob skill. Even with level 1 Triple Stab, on mobs of three, the total DPS is still better than maxed Fatal Blow.

What should be learned from this is the proper usage of each skill; despite doing less single target DPS, Triple Stab is significantly faster and can be used to finish off a monster weakened from Fatal Blow, or weaken a monster enough to finish with Fatal Blow.

Upper Stab
Fatal Blow & Triple Stab

 Spoiler

Upper Stab is learned in Job III+. Upper Stab has the same mechanics as Final Toss for Arans. When used on monsters, it tosses them into the air. While in the air, monsters will take extra damage. It has an exceptionally fast execution time, making this an easy benefit to damage.
+x% damage is added to each hit of an attack while the monster is in the air. It is unknown how long a monster stays in the air, but at least one hit should be able to be done. Below is a chart for Fatal Blow and Triple Stab's DPS changes with Upper Stab included, as well as the damage from Upper Stab itself.

 DPS Chart

Lv	Fatal Blow	Weapon DPS	Blade DPS	DPS	Triple Stab	Weapon DPS	Blade DPS	DPS	3 Mob DPS
1	Fatal Blow	484.00%/s	411.25%/s	36552.22	Triple Stab	454.81%/s	171.85%/s	27540.08	82620.24
2	Fatal Blow	490.30%/s	415.13%/s	36981.48	Triple Stab	461.48%/s	173.33%/s	27910.85	83732.54
3	Fatal Blow	496.61%/s	419.01%/s	37410.75	Triple Stab	468.15%/s	174.81%/s	28281.61	84844.84
4	Fatal Blow	502.91%/s	422.89%/s	37840.01	Triple Stab	474.81%/s	176.30%/s	28652.38	85957.14
5	Fatal Blow	509.21%/s	426.77%/s	38269.28	Triple Stab	481.48%/s	177.78%/s	29023.15	87069.44
6	Fatal Blow	515.52%/s	430.65%/s	38698.54	Triple Stab	488.15%/s	179.26%/s	29393.91	88181.74
7	Fatal Blow	521.82%/s	434.53%/s	39127.81	Triple Stab	494.81%/s	180.74%/s	29764.68	89294.04
8	Fatal Blow	528.13%/s	438.41%/s	39557.07	Triple Stab	501.48%/s	182.22%/s	30135.45	90406.34
9	Fatal Blow	534.43%/s	442.29%/s	39986.34	Triple Stab	508.15%/s	183.70%/s	30506.21	91518.64
10	Fatal Blow	540.74%/s	446.17%/s	40415.60	Triple Stab	514.81%/s	185.19%/s	30876.98	92630.94
11	Fatal Blow	547.04%/s	450.05%/s	40844.87	Triple Stab	521.48%/s	186.67%/s	31247.75	93743.24
12	Fatal Blow	553.35%/s	453.93%/s	41274.13	Triple Stab	528.15%/s	188.15%/s	31618.51	94855.54
13	Fatal Blow	559.65%/s	457.81%/s	41703.40	Triple Stab	534.81%/s	189.63%/s	31989.28	95967.84
14	Fatal Blow	565.96%/s	461.69%/s	42132.66	Triple Stab	541.48%/s	191.11%/s	32360.05	97080.14
15	Fatal Blow	572.26%/s	465.57%/s	42561.93	Triple Stab	548.15%/s	192.59%/s	32730.81	98192.44
16	Fatal Blow	578.56%/s	469.45%/s	42991.20	Triple Stab	554.81%/s	194.07%/s	33101.58	99304.74
17	Fatal Blow	584.87%/s	473.33%/s	43420.46	Triple Stab	561.48%/s	195.56%/s	33472.35	100417.04
18	Fatal Blow	591.17%/s	477.21%/s	43849.73	Triple Stab	568.15%/s	197.04%/s	33843.11	101529.34
19	Fatal Blow	597.48%/s	481.09%/s	44278.99	Triple Stab	574.81%/s	198.52%/s	34213.88	102641.64
20	Fatal Blow	603.78%/s	484.97%/s	44708.26	Triple Stab	581.48%/s	200.00%/s	34584.65	103753.94

 With Critical Ring

Lv	Fatal Blow	Weapon DPS	Blade DPS	DPS	Triple Stab	Weapon DPS	Blade DPS	DPS	3 Mob DPS
1	Fatal Blow	488.36%/s	413.19%/s	36825.73	Triple Stab	457.04%/s	172.59%/s	27743.45	83014.51
2	Fatal Blow	494.67%/s	417.07%/s	37255.00	Triple Stab	463.70%/s	174.07%/s	28114.22	84126.81
3	Fatal Blow	500.97%/s	420.95%/s	37684.26	Triple Stab	470.37%/s	175.56%/s	28484.99	85239.11
4	Fatal Blow	507.27%/s	424.83%/s	38113.53	Triple Stab	477.04%/s	177.04%/s	28855.75	86351.41
5	Fatal Blow	513.58%/s	428.71%/s	38542.79	Triple Stab	483.70%/s	178.52%/s	29226.52	87463.71
6	Fatal Blow	519.88%/s	432.59%/s	38972.06	Triple Stab	490.37%/s	180.00%/s	29597.29	88576.01
7	Fatal Blow	526.19%/s	436.47%/s	39401.32	Triple Stab	497.04%/s	181.48%/s	29968.05	89688.31
8	Fatal Blow	532.49%/s	440.35%/s	39830.59	Triple Stab	503.70%/s	182.96%/s	30338.82	90800.61
9	Fatal Blow	538.80%/s	444.23%/s	40259.85	Triple Stab	510.37%/s	184.44%/s	30709.59	91912.91
10	Fatal Blow	545.10%/s	448.11%/s	40689.12	Triple Stab	517.04%/s	185.93%/s	31080.35	93025.21
11	Fatal Blow	551.41%/s	451.99%/s	41118.38	Triple Stab	523.70%/s	187.41%/s	31451.12	94137.51
12	Fatal Blow	557.71%/s	455.87%/s	41547.65	Triple Stab	530.37%/s	188.89%/s	31821.89	95249.81
13	Fatal Blow	564.02%/s	459.75%/s	41976.91	Triple Stab	537.04%/s	190.37%/s	32192.65	96362.11
14	Fatal Blow	570.32%/s	463.63%/s	42406.18	Triple Stab	543.70%/s	191.85%/s	32563.42	97474.41
15	Fatal Blow	576.62%/s	467.51%/s	42835.44	Triple Stab	550.37%/s	193.33%/s	32934.19	98586.71
16	Fatal Blow	582.93%/s	471.39%/s	43264.71	Triple Stab	557.04%/s	194.81%/s	33304.95	99699.01
17	Fatal Blow	589.23%/s	475.27%/s	43693.97	Triple Stab	563.70%/s	196.30%/s	33675.72	100811.31
18	Fatal Blow	595.54%/s	479.15%/s	44123.24	Triple Stab	570.37%/s	197.78%/s	34046.49	101923.61
19	Fatal Blow	601.84%/s	483.03%/s	44552.50	Triple Stab	577.04%/s	199.26%/s	34417.25	103035.91
20	Fatal Blow	608.15%/s	486.91%/s	44981.77	Triple Stab	583.70%/s	200.74%/s	34788.02	104148.21

Although we can clearly see the vast difference in DPS output, where Fatal Blow is greater than Triple stab on all accounts, Triple Stab does still provide a major boost in mob DPS that Fatal Blow cannot.
Incidentally, it is an improvement to use Upper Stab + Fatal Blow compared to only Fatal Blow even with level 1 Upper Stab.

Triple Stab vs Slash and Bloody Storm vs Tornado Spin vs Flying Assaulter
Primary Mob Skills

 Triple Stab

Lv	Dagger	Blade	DPS	Mob DPS
10	459.77%/s	229.89%/s	29621.84	88865.52

Taking a quick look at this first and comparing with other skills available later, you can note that DPS is straight out higher. Thus, we can conclude that per mob, Triple Stab is stronger. For 1~3 (though you should be using Fatal Blow or Chains of Hell) for 1 mob, Triple Stab does more DPS than Slash/Bloody Storm, Upper Stab, Tornado Spin, and Flying Assaulter.

What Triple Stab has to its advantage compared to the other skills is its speed, and its ability to hit three times. A significant focus on the Dagger DPS gives it a higher output compared to even Dagger/Blade distributions from the other skills due to the Blade being quite a bit weaker than the Dagger almost universally. The disadvantage is the limit of three mobs, but it proves to be a better DPS skill. Combined with Upper Stab, you get three hits that gain the damage bonus instead of two. Combined with Mirror Image, the same occurs, as well as with Thorns.

Triple Stab also does not force the Dual Blade to move after attacking, allowing for mob pinning, and situations where attacks such as Bloody Storm cannot be used (perhaps a wall, cliff, or other dangers).

 Slash and Bloody Storm

Slash Storm is the second mob skill learned by Dualers. It is acquirable at level 30 in their II+ Job.
Both Slash and Bloody Storm attack twice. The bottom number is the Dagger hit, and the top number is the Blade hit.
Slash and Bloody Storm cause the character to move forward across a distance when they attack, similar to Assaulter in that it does not rush monsters forward with them. They have invincibility frames until the attack stops, unlike Fatal Blow where you can still be hit in the animation.
Bloody Storm requires 20 Slash Storm as a prerequisite.
Bloody Storm is earned at Job III+ at level 70, and has 10 levels of mastery. It can also hit up to 8 monsters. Points from Job III can be saved up in advanced for Bloody Storm.

	Time (ms)
slashStorm1	600
slashStorm2	720
bloodyStorm	810

Given the base speed of 600ms, Slash Storm does 163.33%/s Dagger and Blade Base DPS to up to three targets at level 1. At max level, this changes to 222.22%/s Dagger + Blade to six targets with a base speed of 720ms.
What's important to note here is that Slash Storm does become slower at a higher level. At level 11, it switches from using slashStorm1 to slashStorm2 as its delay. Thus, its DPS is lowered slightly, though it gains the ability to mob one more target as well as a range increase.
This should be taken into consideration when leveling this skill as it may slightly change training patterns and efficiencies. Another odd point to note is that only level 12 Slash Storm has 5% more range than 11~20. 5% is not particularly far, but it is an improvement and could be taken into consideration when planning.

Another interesting point exists in Slash Storm's damage table. Level 6~8 has a 5~10% damage difference per point compared to 2~3% for every other level, AND level 6 from level 5 has a huge 14% damage difference. Thus the point going into level 6 up to level 8 Slash Storm provides a much higher damage efficiency improvement for skill point use, and you can noticeably see the significant DPS%/s difference at these points.

 Slash Storm DPS Chart

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	163.33%/s	13114.03	3	39342.10
2	166.67%/s	13381.67	3	40145.00
3	170.00%/s	13649.30	3	40947.90
4	173.33%/s	13916.93	3	41750.80
5	176.67%/s	14184.57	3	42553.70
6	200.00%/s	16058.00	4	64232.00
7	208.33%/s	16727.08	4	66908.33
8	216.67%/s	17396.17	4	69584.67
9	220.00%/s	17663.80	4	70655.20
10	225.00%/s	18065.25	4	72261.00
11	190.28%/s	15277.40	5	76387.01
12	194.44%/s	15611.94	5	78059.72
13	197.22%/s	15834.97	5	79174.86
14	201.39%/s	16169.51	5	80847.57
15	204.17%/s	16392.54	5	81962.71
16	208.33%/s	16727.08	6	100362.50
17	211.11%/s	16950.11	6	101700.67
18	215.28%/s	17284.65	6	103707.92
19	218.06%/s	17507.68	6	105046.08
20	222.22%/s	17842.22	6	107053.33

 With Critical Ring

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	165.00%/s	13247.85	3	39743.55
2	168.33%/s	13515.48	3	40546.45
3	171.67%/s	13783.12	3	41349.35
4	175.00%/s	14050.75	3	42152.25
5	178.33%/s	14318.38	3	42955.15
6	201.67%/s	16191.82	4	64767.27
7	210.00%/s	16860.90	4	67443.60
8	218.33%/s	17529.98	4	70119.93
9	221.67%/s	17797.62	4	71190.47
10	226.67%/s	18199.07	4	72796.27
11	191.67%/s	15388.92	5	76944.58
12	195.83%/s	15723.46	5	78617.29
13	198.61%/s	15946.49	5	79732.43
14	202.78%/s	16281.03	5	81405.14
15	205.56%/s	16504.06	5	82520.28
16	209.72%/s	16838.60	6	101031.58
17	212.50%/s	17061.62	6	102369.75
18	216.67%/s	17396.17	6	104377.00
19	219.44%/s	17619.19	6	105715.17
20	223.61%/s	17953.74	6	107722.42

Bloody Storm is an interesting change. At level 1~5, it appears to attack six enemies, equal to Slash Storm at max level. Whether this is a typo or an intended feature is yet to be determined, as level 6~10 hit eight enemies, as well as having its range improved even further.
Bloody Storm not only has improved horizontal range, its vertical is slightly taller as well. At level 6, its horizontal is 300%, which proves to be nearly 1.5x longer than Slash Storm. The damage improves at level 1 from Slash Storm's 160% to 190%, giving 234.57%/s Dagger + Blade DPS which is an improvement (remember this is for both ranges).
Oddly enough, maxed Bloody Storm's range is 280%, 20% shorter than level 9 Bloody Storm.
At max level, Bloody Storm provides 345.68%/s Dagger + Blade DPS to eight targets, over 1.5x stronger than Slash Storm

 Bloody Storm DPS Chart

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	234.57%/s	18833.46	6	113000.74
2	246.91%/s	19824.69	6	118948.15
3	259.26%/s	20815.93	6	124895.56
4	271.60%/s	21807.16	6	130842.96
5	283.95%/s	22798.40	6	136790.37
6	296.30%/s	23789.63	8	190317.04
7	308.64%/s	24780.86	8	198246.91
8	320.99%/s	25772.10	8	206176.79
9	333.33%/s	26763.33	8	214106.67
10	345.68%/s	27754.57	8	222036.54

 With Critical Ring

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	235.80%/s	18932.58	6	113595.48
2	248.15%/s	19923.81	6	119542.89
3	260.49%/s	20915.05	6	125490.30
4	272.84%/s	21906.28	6	131437.70
5	285.19%/s	22897.52	6	137385.11
6	297.53%/s	23888.75	8	191110.02
7	309.88%/s	24879.99	8	199039.90
8	322.22%/s	25871.22	8	206969.78
9	334.57%/s	26862.46	8	214899.65
10	346.91%/s	27853.69	8	222829.53

Taking Triple Stab into consideration, we see that it does out damage Slash Storm comparatively with similar and maxed mobs. As advantageous as the extra damage may be, Slash Storm does provide the inexpendable ability to gather mobs, if not only to kill large groups. Both advantages should be taken into consideration when planning, and it should be thoroughly noted that Bloody Storm is still superior to Triple Stab on four or higher mobs, due to its ability to hit much higher amounts of monsters, and its superior range as well as speed.

 Tornado Spin

From what I'm understanding of the skill so far, you double tap a direction and you enter a state of Tornado Spin. Presumably, you move foward with enhanced speed in this state. Lasting one second, while in this state, you can press the attack key to activate the attacking portion of Tornado Spin.
Tornado Spin is obtainable at level 55 in Job III.
Tornado Spin provides 152% damage to three enemies at level 1. It appears as a step down from Slash Storm in terms of damage, but likely has mobility advantages not seen in DPS, much like uncharged Corkscrew Punching.

	Time (ms)
tornadoDash	180
tornadoRush	960
tornadoDashStop	400

With this mechanic, there is a small buffer time on activating the Dash sequence.
Tornado Rush itself as an attack takes 960ms Base, so it would appear to be slower than Slash or Bloody Storm. TornadoDash would most likely not have its speed reduced by Booster or Weapon Speed, but it is still a possibility. It likely has a cool down or delay time after usage, like most movement skills, as well as taking a large portion of your MP to add to its possible disadvantages. I also presume that Dash Stop is an alternative action to Rush. i.e. you can Dash Stop instead of Rushing and doing damage.
Tornado Spin does push monsters forward with you, and thus becomes fundamental in gathering mobs for training. A minimum level of 16 is recommended going into Job III+

Like Slash Storm, Tornado Spin gets an interesting +20% increase at level 6 instead of +2% from before or the +5% afterwards, making this a very significant improvement for damage.

 Tornado Spin DPS Chart

Lv	Dagger DPS	DPS	Mob	Mob DPS
1	133.33%/s	6475.33	3	19426.00
2	135.09%/s	6560.54	3	19681.61
3	136.84%/s	6645.74	3	19937.21
4	138.60%/s	6730.94	3	20192.82
5	140.35%/s	6816.14	3	20448.42
6	149.12%/s	7242.15	4	28968.60
7	153.51%/s	7455.15	4	29820.61
8	157.89%/s	7668.16	4	30672.63
9	162.28%/s	7881.16	4	31524.65
10	166.67%/s	8094.17	4	32376.67
11	171.05%/s	8307.17	5	41535.86
12	175.44%/s	8520.18	5	42600.88
13	179.82%/s	8733.18	5	43665.90
14	184.21%/s	8946.18	5	44730.92
15	188.60%/s	9159.19	5	45795.94
16	192.98%/s	9372.19	8	74977.54
17	197.37%/s	9585.20	8	76681.58
18	201.75%/s	9798.20	8	78385.61
19	206.14%/s	10011.21	8	80089.65
20	210.53%/s	10224.21	8	81793.68

 With Critical Ring

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	134.21%/s	6517.93	3	19553.80
2	135.96%/s	6603.14	3	19809.41
3	137.72%/s	6688.34	3	20065.01
4	139.47%/s	6773.54	3	20320.62
5	141.23%/s	6858.74	3	20576.22
6	150.00%/s	7284.75	4	29139.00
7	154.39%/s	7497.75	4	29991.02
8	158.77%/s	7710.76	4	30843.04
9	163.16%/s	7923.76	4	31695.05
10	167.54%/s	8136.77	4	32547.07
11	171.93%/s	8349.77	5	41748.86
12	176.32%/s	8562.78	5	42813.88
13	180.70%/s	8775.78	5	43878.90
14	185.09%/s	8988.79	5	44943.93
15	189.47%/s	9201.79	5	46008.95
16	193.86%/s	9414.79	8	75318.35
17	198.25%/s	9627.80	8	77022.39
18	202.63%/s	9840.80	8	78726.42
19	207.02%/s	10053.81	8	80430.46
20	211.40%/s	10266.81	8	82134.49

With the information presented here, we can conclude that Tornado Spin is not a premier DPS skill. Its value would appear to lie in its rushing mechanic in gathering mobs as well as traveling, allowing for the use of other mob skills to greater effect. At its level range in learning, it also provides a method of hitting up to eight targets.

 Flying Assaulter

Flying Assaulter is learned in Job III+ like Bloody Storm. It starts at four mobs with 160% damage and works its way up to eight mobs and 400% damage with more range than Bloody Storm.
It requires maxed Self Haste and as such, presumably 123% Jump Rating at full height to be used, and it appears it cannot be used going up a slope.
It can however be otherwise used to travel distances like Recoil Shot for Gunslingers, such as being used in midair after a Flash Jump.
Another important factor to note is Flying Assaulter rushes monsters. Combined with Upper Stab's damage improving toss and fast speed, the two can be used to gather and finish mobs quickly that would otherwise be more difficult to deal with using Bloody Storm's movement or Triple Stab's mob limit.
At max level, it provides a theoretical 289.9%/s Dagger + Blade DPS, lower than Bloody Storm; however, it also appears to have a slight delay as well as requiring a jump. I personally measured a ~100% jump to be around 600ms. Adding that to the Base Speed of Flying Assaulter, we have 1980ms, 600+ of which cannot be reduced with Booster due to it being a part of the jump action. Other jobs have proved to us, however, that sheer DPS on mobs is not the only constant factor, as gather mobs quickly with a rush skill provides countless benefits in training.

 Flying Assaulter Base DPS Chart

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	80.81%/s	6488.08	4	25952.32
2	83.33%/s	6690.83	4	26763.33
3	85.86%/s	6893.59	4	27574.34
4	88.38%/s	7096.34	4	28385.35
5	90.91%/s	7299.09	4	29196.36
6	106.06%/s	8515.61	5	42578.03
7	111.11%/s	8921.11	5	44605.56
8	116.16%/s	9326.62	5	46633.08
9	121.21%/s	9732.12	5	48660.61
10	126.26%/s	10137.63	5	50688.13
11	133.84%/s	10745.88	6	64475.30
12	141.41%/s	11354.14	6	68124.85
13	148.99%/s	11962.40	6	71774.39
14	156.57%/s	12570.66	6	75423.94
15	164.14%/s	13178.91	6	79073.48
16	171.72%/s	13787.17	8	110297.37
17	179.29%/s	14395.43	8	115163.43
18	186.87%/s	15003.69	8	120029.49
19	194.44%/s	15611.94	8	124895.56
20	202.02%/s	16220.20	8	129761.62

 With Critical Ring

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	81.31%/s	6528.63	4	26114.53
2	83.84%/s	6731.38	4	26925.54
3	86.36%/s	6934.14	4	27736.55
4	88.89%/s	7136.89	4	28547.56
5	91.41%/s	7339.64	4	29358.57
6	106.57%/s	8556.16	5	42780.78
7	111.62%/s	8961.66	5	44808.31
8	116.67%/s	9367.17	5	46835.83
9	121.72%/s	9772.67	5	48863.36
10	126.77%/s	10178.18	5	50890.88
11	134.34%/s	10786.43	6	64718.61
12	141.92%/s	11394.69	6	68368.15
13	149.49%/s	12002.95	6	72017.70
14	157.07%/s	12611.21	6	75667.24
15	164.65%/s	13219.46	6	79316.79
16	172.22%/s	13827.72	8	110621.78
17	179.80%/s	14435.98	8	115487.84
18	187.37%/s	15044.24	8	120353.90
19	194.95%/s	15652.49	8	125219.96
20	202.53%/s	16260.75	8	130086.02

Seeing the DPS table, it's obvious that it is a large benefit over Tornado Spin in terms of damage dealt while rushing. The two can be combined in usage though to either collect a larger mob or move to a more desirable location to finish attacking, and Tornado Spin still has its own use in areas where Flying Assaulter is either inconvenient or impossible.

 Upper Stab

Upper Stab provides mob damage with exceptional speed. Its base speed is 480ms, giving it incredible spammability. Combined with improved damage on at least every second hit, it wracks up a lot of damage. It is currently unknown if it is possible to hit more than once with Upper Stab after launching, but with its speed, it could happen, raising the damage bar even more. As seen with an Aran, the ability to juggle a monster can durastically increase damage output, but Dual Blades lack the Smart Knockback ability to maintain this consistency on stronger monsters. At the very least, Upper Stab can toss a monster and hit it at least once before it falls back to the ground.
Upper Stab only does one hit, so it only uses the Dagger Range, but it has such high speeds that it has a large DPS output either way. It is only hindered by its max mob size of six, and would otherwise out-DPS Bloody Storm.

 Upper Stab DPS Chart

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	345.83%/s	16795.40	3	50386.19
2	358.33%/s	17402.46	3	52207.38
3	370.83%/s	18009.52	3	54028.56
4	383.33%/s	18616.58	3	55849.75
5	395.83%/s	19223.65	3	57670.94
6	408.33%/s	19830.71	4	79322.83
7	420.83%/s	20437.77	4	81751.08
8	433.33%/s	21044.83	4	84179.33
9	445.83%/s	21651.90	4	86607.58
10	458.33%/s	22258.96	4	89035.83
11	470.83%/s	22866.02	5	114330.10
12	483.33%/s	23473.08	5	117365.42
13	495.83%/s	24080.15	5	120400.73
14	508.33%/s	24687.21	5	123436.04
15	520.83%/s	25294.27	5	126471.35
16	533.33%/s	25901.33	6	155408.00
17	545.83%/s	26508.40	6	159050.38
18	558.33%/s	27115.46	6	162692.75
19	570.83%/s	27722.52	6	166335.12
20	583.33%/s	28329.58	6	169977.50

 With Critical Ring

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	347.92%/s	16896.57	3	50689.72
2	360.42%/s	17503.64	3	52510.91
3	372.92%/s	18110.70	3	54332.09
4	385.42%/s	18717.76	3	56153.28
5	397.92%/s	19324.82	3	57974.47
6	410.42%/s	19931.89	4	79727.54
7	422.92%/s	20538.95	4	82155.79
8	435.42%/s	21146.01	4	84584.04
9	447.92%/s	21753.07	4	87012.29
10	460.42%/s	22360.14	4	89440.54
11	472.92%/s	22967.20	5	114835.99
12	485.42%/s	23574.26	5	117871.30
13	497.92%/s	24181.32	5	120906.61
14	510.42%/s	24788.39	5	123941.93
15	522.92%/s	25395.45	5	126977.24
16	535.42%/s	26002.51	6	156015.06
17	547.92%/s	26609.57	6	159657.44
18	560.42%/s	27216.64	6	163299.81
19	572.92%/s	27823.70	6	166942.19
20	585.42%/s	28430.76	6	170584.56

Upper Stab
Mob Skill Combinations

 Spoiler

The following are tables containing the various mob skills available to the Dual Blade, along with the level of Upper Stab.
With these, we can determine the advantageous effects of mastering and using Upper Stab effectively.

 Triple Upper DPS Table

Lv	Triple Stab	Dagger DPS	Blade DPS	DPS	3 Mob DPS
1	Triple Stab	454.81%/s	171.85%/s	27540.08	82620.24
2	Triple Stab	461.48%/s	173.33%/s	27910.85	83732.54
3	Triple Stab	468.15%/s	174.81%/s	28281.61	84844.84
4	Triple Stab	474.81%/s	176.30%/s	28652.38	85957.14
5	Triple Stab	481.48%/s	177.78%/s	29023.15	87069.44
6	Triple Stab	488.15%/s	179.26%/s	29393.91	88181.74
7	Triple Stab	494.81%/s	180.74%/s	29764.68	89294.04
8	Triple Stab	501.48%/s	182.22%/s	30135.45	90406.34
9	Triple Stab	508.15%/s	183.70%/s	30506.21	91518.64
10	Triple Stab	514.81%/s	185.19%/s	30876.98	92630.94
11	Triple Stab	521.48%/s	186.67%/s	31247.75	93743.24
12	Triple Stab	528.15%/s	188.15%/s	31618.51	94855.54
13	Triple Stab	534.81%/s	189.63%/s	31989.28	95967.84
14	Triple Stab	541.48%/s	191.11%/s	32360.05	97080.14
15	Triple Stab	548.15%/s	192.59%/s	32730.81	98192.44
16	Triple Stab	554.81%/s	194.07%/s	33101.58	99304.74
17	Triple Stab	561.48%/s	195.56%/s	33472.35	100417.04
18	Triple Stab	568.15%/s	197.04%/s	33843.11	101529.34
19	Triple Stab	574.81%/s	198.52%/s	34213.88	102641.64
20	Triple Stab	581.48%/s	200.00%/s	34584.65	103753.94

 Slash & Bloody Storm

 Upper Slash DPS Table

Lv	Dagger DPS	Blade DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	285.00%/s	160.00%/s	18917.02	3	56751.08	95290.28
2	290.83%/s	161.67%/s	19253.20	3	57759.59	96700.24
3	296.67%/s	163.33%/s	19589.37	3	58768.10	98110.20
4	302.50%/s	165.00%/s	19925.54	3	59776.61	99520.16
5	308.33%/s	166.67%/s	20261.71	3	60785.12	100930.12
6	314.17%/s	168.33%/s	20597.88	4	82391.52	109422.48
7	320.00%/s	170.00%/s	20934.05	4	83736.20	111034.80
8	325.83%/s	171.67%/s	21270.22	4	85080.88	112647.12
9	331.67%/s	173.33%/s	21606.39	4	86425.57	114259.43
10	337.50%/s	175.00%/s	21942.56	4	87770.25	115871.75
11	343.33%/s	176.67%/s	22278.73	5	111393.67	125578.23
12	349.17%/s	178.33%/s	22614.90	5	113074.52	127392.90
13	355.00%/s	180.00%/s	22951.08	5	114755.38	129207.58
14	360.83%/s	181.67%/s	23287.25	5	116436.23	131022.25
15	366.67%/s	183.33%/s	23623.42	5	118117.08	132836.92
16	372.50%/s	185.00%/s	23959.59	6	143757.52	143757.52
17	378.33%/s	186.67%/s	24295.76	6	145774.55	145774.55
18	384.17%/s	188.33%/s	24631.93	6	147791.58	147791.58
19	390.00%/s	190.00%/s	24968.10	6	149808.60	149808.60
20	395.83%/s	191.67%/s	25304.27	6	151825.62	151825.62

 Bloody Upper DPS Table

 Level 1 Bloody Storm

Lv	Dagger DPS	Blade DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	288.37%/s	172.09%/s	19464.44	3	58393.33	99845.37
2	293.80%/s	173.64%/s	19777.16	3	59331.48	101156.97
3	299.22%/s	175.19%/s	20089.88	3	60269.63	102468.56
4	304.65%/s	176.74%/s	20402.59	3	61207.78	103780.15
5	310.08%/s	178.29%/s	20715.31	3	62145.93	105091.74
6	315.50%/s	179.84%/s	21028.03	4	84112.11	112991.61
7	320.93%/s	181.40%/s	21340.74	4	85362.98	114491.44
8	326.36%/s	182.95%/s	21653.46	4	86613.84	115991.27
9	331.78%/s	184.50%/s	21966.18	4	87864.71	117491.10
10	337.21%/s	186.05%/s	22278.90	4	89115.58	118990.93
11	342.64%/s	187.60%/s	22591.61	5	112958.06	128020.22
12	348.06%/s	189.15%/s	22904.33	5	114521.65	129708.28
13	353.49%/s	190.70%/s	23217.05	5	116085.23	131396.35
14	358.91%/s	192.25%/s	23529.76	5	117648.82	133084.41
15	364.34%/s	193.80%/s	23842.48	5	119212.40	134772.48
16	369.77%/s	195.35%/s	24155.20	6	144931.19	144931.19
17	375.19%/s	196.90%/s	24467.91	6	146807.49	146807.49
18	380.62%/s	198.45%/s	24780.63	6	148683.79	148683.79
19	386.05%/s	200.00%/s	25093.35	6	150560.09	150560.09
20	391.47%/s	201.55%/s	25406.07	6	152436.40	152436.40

 Level 10 Bloody Storm

Lv	Dagger DPS	Blade DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	358.14%/s	241.86%/s	25066.07	3	75198.21	172293.09
2	363.57%/s	243.41%/s	25378.79	3	76136.36	173853.65
3	368.99%/s	244.96%/s	25691.50	3	77074.51	175414.20
4	374.42%/s	246.51%/s	26004.22	3	78012.66	176974.76
5	379.84%/s	248.06%/s	26316.94	3	78950.81	178535.31
6	385.27%/s	249.61%/s	26629.66	4	106518.62	186684.14
7	390.70%/s	251.16%/s	26942.37	4	107769.49	188432.93
8	396.12%/s	252.71%/s	27255.09	4	109020.36	190181.72
9	401.55%/s	254.26%/s	27567.81	4	110271.22	191930.51
10	406.98%/s	255.81%/s	27880.52	4	111522.09	193679.30
11	412.40%/s	257.36%/s	28193.24	5	140966.20	202957.55
12	417.83%/s	258.91%/s	28505.96	5	142529.79	204894.58
13	423.26%/s	260.47%/s	28818.67	5	144093.37	206831.60
14	428.68%/s	262.02%/s	29131.39	5	145656.96	208768.63
15	434.11%/s	263.57%/s	29444.11	5	147220.54	210705.66
16	439.53%/s	265.12%/s	29756.83	6	178540.95	221113.33
17	444.96%/s	266.67%/s	30069.54	6	180417.26	223238.59
18	450.39%/s	268.22%/s	30382.26	6	182293.56	225363.85
19	455.81%/s	269.77%/s	30694.98	6	184169.86	227489.12
20	461.24%/s	271.32%/s	31007.69	6	186046.16	229614.38

 Tornado Spin

Lv	Dagger DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	266.67%/s	12950.67	3	38852.00	81121.54
2	270.99%/s	13160.52	3	39481.55	82050.87
3	275.31%/s	13370.36	3	40111.09	82980.20
4	279.63%/s	13580.21	3	40740.64	83909.53
5	283.95%/s	13790.06	3	41370.19	84838.86
6	288.27%/s	13999.91	4	55999.64	91014.41
7	292.59%/s	14209.76	4	56839.04	92093.63
8	296.91%/s	14419.61	4	57678.43	93172.85
9	301.23%/s	14629.46	4	58517.83	94252.07
10	305.56%/s	14839.31	4	59357.22	95331.30
11	309.88%/s	15049.15	5	75245.77	102406.20
12	314.20%/s	15259.00	5	76295.02	103635.31
13	318.52%/s	15468.85	5	77344.26	104864.43
14	322.84%/s	15678.70	5	78393.50	106093.54
15	327.16%/s	15888.55	5	79442.75	107322.65
16	331.48%/s	16098.40	6	96590.39	115296.91
17	335.80%/s	16308.25	6	97849.48	116675.91
18	340.12%/s	16518.10	6	99108.57	118054.92
19	344.44%/s	16727.94	6	100367.67	119433.93
20	348.77%/s	16937.79	6	101626.76	120812.93

 Flying Upper DPS Table

 Level 11 Flying Assaulter

Lv	Dagger DPS	Blade DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	181.71%/s	120.73%/s	12654.83	3	37964.49	67045.13
2	184.55%/s	121.54%/s	12818.82	3	38456.45	67732.92
3	187.40%/s	122.36%/s	12982.80	3	38948.40	68420.71
4	190.24%/s	123.17%/s	13146.79	3	39440.36	69108.49
5	193.09%/s	123.98%/s	13310.77	3	39932.32	69796.28
6	195.93%/s	124.80%/s	13474.76	4	53899.03	73938.89
7	198.78%/s	125.61%/s	13638.74	4	54554.98	74725.39
8	201.63%/s	126.42%/s	13802.73	4	55210.92	75511.89
9	204.47%/s	127.24%/s	13966.72	4	55866.86	76298.38
10	207.32%/s	128.05%/s	14130.70	4	56522.80	77084.88
11	210.16%/s	128.86%/s	14294.69	5	71473.43	81819.75
12	213.01%/s	129.67%/s	14458.67	5	72293.36	82704.95
13	215.85%/s	130.49%/s	14622.66	5	73113.29	83590.16
14	218.70%/s	131.30%/s	14786.64	5	73933.22	84475.36
15	221.54%/s	132.11%/s	14950.63	5	74753.15	85360.57
16	224.39%/s	132.93%/s	15114.62	6	90687.70	90687.70
17	227.24%/s	133.74%/s	15278.60	6	91671.61	91671.61
18	230.08%/s	134.55%/s	15442.59	6	92655.52	92655.52
19	232.93%/s	135.37%/s	15606.57	6	93639.44	93639.44
20	235.77%/s	136.18%/s	15770.56	6	94623.35	94623.35

 Level 20 Flying Assaulter

Lv	Dagger DPS	Blade DPS	DPS Per Mob	Mob	Same Mob	Max Mob
1	236.59%/s	175.61%/s	17060.99	3	51182.96	121681.50
2	239.43%/s	176.42%/s	17224.97	3	51674.92	122499.84
3	242.28%/s	177.24%/s	17388.96	3	52166.88	123318.18
4	245.12%/s	178.05%/s	17552.95	3	52658.84	124136.52
5	247.97%/s	178.86%/s	17716.93	3	53150.79	124954.86
6	250.81%/s	179.67%/s	17880.92	4	71523.67	129228.02
7	253.66%/s	180.49%/s	18044.90	4	72179.61	130145.07
8	256.50%/s	181.30%/s	18208.89	4	72835.55	131062.12
9	259.35%/s	182.11%/s	18372.87	4	73491.50	131979.17
10	262.20%/s	182.93%/s	18536.86	4	74147.44	132896.22
11	265.04%/s	183.74%/s	18700.85	5	93504.23	137761.64
12	267.89%/s	184.55%/s	18864.83	5	94324.16	138777.40
13	270.73%/s	185.37%/s	19028.82	5	95144.09	139793.16
14	273.58%/s	186.18%/s	19192.80	5	95964.01	140808.92
15	276.42%/s	186.99%/s	19356.79	5	96783.94	141824.67
16	279.27%/s	187.80%/s	19520.77	6	117124.65	147282.35
17	282.11%/s	188.62%/s	19684.76	6	118108.56	148396.82
18	284.96%/s	189.43%/s	19848.75	6	119092.48	149511.29
19	287.80%/s	190.24%/s	20012.73	6	120076.39	150625.76
20	290.65%/s	191.06%/s	20176.72	6	121060.30	151740.22

 Upper Stab DPS Chart

Lv	Weapon DPS	DPS	Mob	Mob DPS
1	345.83%/s	16795.40	3	50386.19
2	358.33%/s	17402.46	3	52207.38
3	370.83%/s	18009.52	3	54028.56
4	383.33%/s	18616.58	3	55849.75
5	395.83%/s	19223.65	3	57670.94
6	408.33%/s	19830.71	4	79322.83
7	420.83%/s	20437.77	4	81751.08
8	433.33%/s	21044.83	4	84179.33
9	445.83%/s	21651.90	4	86607.58
10	458.33%/s	22258.96	4	89035.83
11	470.83%/s	22866.02	5	114330.10
12	483.33%/s	23473.08	5	117365.42
13	495.83%/s	24080.15	5	120400.73
14	508.33%/s	24687.21	5	123436.04
15	520.83%/s	25294.27	5	126471.35
16	533.33%/s	25901.33	6	155408.00
17	545.83%/s	26508.40	6	159050.38
18	558.33%/s	27115.46	6	162692.75
19	570.83%/s	27722.52	6	166335.12
20	583.33%/s	28329.58	6	169977.50

Taking a look at the tables, we can conclude the final DPS output and theoretical best skill in terms of damaging mobs.
Of all the output aside from Upper Stab alone, Level 1 Bloody Storm with any level of Upper Stab appears to provide the highest DPS in terms of matching and maxed mob (i.e. same number of monsters as Upper Stab can hit compared to the max number of monsters Bloody Storm can hit).
However, Triple Stab alone does more DPS, and is only beaten by its own Upper Stab combination when Upper Stab reaches level 7.
Maxed Bloody Storm proves to be the highest DPS of the mob skills available, though Flying Assaulter provides the benefit of rushing monsters; however, second place belongs to Upper Stab alone as it can be used to toss monsters and then damage them quickly, providing the second highest DPS for mob skills available.
This analysis does not take into consideration the ability to toss mobs a second time after using Bloody Storm. Since Bloody Storm causes the Dual Blader to run forward, through the monsters, it may be likely they become out of range from being able to Upper Stab once more afterwards, requiring them to readjust their position or use a different skill to rush the mob back together.
It may very well be possible to use multiple skills in quick succession to maintain an otherwise impossible juggle.

Mirror Image

 Spoiler

With recent news coming to light from the 4th Job Single Target DPS Thread, Mirror Image apparently does not scale damage from your skill's attack percent but from your base damage range, thus reducing effectiveness significantly than previously assumed. I will elaborate more on this with time.

What this brings is a very different mechanic compared to Night Lords that throws a much more heavy emphasis on multi-hit skills compared to high% hits, much like Critical. This heavily favours Final Blow and Triple Stab, as well as Chains of Hell more since they get +x% for every hit, whereas other skills only get two +x%s.

Chains of Hell

 Spoiler

Chains of Hell consists of attacking patterns. First, a chain is tossed forward to Snatch a target. If the target is a boss or immobile, this chain will miss and do nothing.
Second, the attack portion occurs, hitting the monster if it is in range. For the most part in training, the Chain will pull a target close enough to be hit with the rest of the attack; however, if you are not close enough against immobile or boss monsters, the rest of the attack will not connect.
To use Chains of Hell, you are required to be in Dark Sight. Advanced Dark Sight helps reduce the delay between each usage as you do not need to recast Dark Sight, taking some time.
With an approximate 120ms Dark Sight, Chains of Hell still appears to have some delay time in its usage, not meeting its expected theoretical speed at 660ms Chain + 1740ms Attack.
Though I can't find the video right now, it showed a Dual Blade using Chains of Hell at approximately 2.3s per usage, giving it roughly 600ms on its base speed in delay. This is of course approximated, however, and is not an exact value. As such, I will be displaying both an optimal and approximated DPS table, not including any Criticals or Mirror Image.
I presume that Upper Stab is not compatible with Chains of Hell as the target would either not be in range to be Chained, or it would be grounded when Chained, though I could be wrong.

 Base DPS Table

 Optimal

Lv	Weapon DPS	DPS
1	476.19%/s	38233.33
2	500.00%/s	40145.00
3	523.81%/s	42056.67
4	547.62%/s	43968.33
5	571.43%/s	45880.00
6	595.24%/s	47791.67
7	619.05%/s	49703.33
8	642.86%/s	51615.00
9	666.67%/s	53526.67
10	690.48%/s	55438.33
11	714.29%/s	57350.00
12	738.10%/s	59261.67
13	761.90%/s	61173.33
14	785.71%/s	63085.00
15	809.52%/s	64996.67
16	833.33%/s	66908.33
17	857.14%/s	68820.00
18	880.95%/s	70731.67
19	904.76%/s	72643.33
20	928.57%/s	74555.00
21	952.38%/s	76466.67
22	976.19%/s	78378.33
23	1000.00%/s	80290.00
24	1023.81%/s	82201.67
25	1047.62%/s	84113.33
26	1071.43%/s	86025.00
27	1095.24%/s	87936.67
28	1119.05%/s	89848.33
29	1142.86%/s	91760.00
30	1190.48%/s	95583.33

 Approximate

Lv	Weapon DPS	DPS
1	384.62%/s	30880.77
2	403.85%/s	32424.81
3	423.08%/s	33968.85
4	442.31%/s	35512.88
5	461.54%/s	37056.92
6	480.77%/s	38600.96
7	500.00%/s	40145.00
8	519.23%/s	41689.04
9	538.46%/s	43233.08
10	557.69%/s	44777.12
11	576.92%/s	46321.15
12	596.15%/s	47865.19
13	615.38%/s	49409.23
14	634.62%/s	50953.27
15	653.85%/s	52497.31
16	673.08%/s	54041.35
17	692.31%/s	55585.38
18	711.54%/s	57129.42
19	730.77%/s	58673.46
20	750.00%/s	60217.50
21	769.23%/s	61761.54
22	788.46%/s	63305.58
23	807.69%/s	64849.62
24	826.92%/s	66393.65
25	846.15%/s	67937.69
26	865.38%/s	69481.73
27	884.62%/s	71025.77
28	903.85%/s	72569.81
29	923.08%/s	74113.85
30	961.54%/s	77201.92

Thorns
The Other SE

 Spoiler

Thorns gives +250% @ a 35% Rate Criticals to Dual Blades at max level. Any class without a natural Critical receives half the damage increase at the same rate.
Thorns is a party buff that does not stack with Sharp Eyes. Archers and Night Lords cannot receive Thorns. Arans and Buccaneers can have Thorns active while their Critical activation rate is lower than Thorns.
A semi-important note is that at level 11, Thorns receives a significantly larger bonus to its +% damage than any other level.

 Triple Stab + Upper Stab + Mirror Image + Thorns

Lv	Dagger DPS	Blade DPS	DPS	Mob DPS
1	504.15%/s	200.22%/s	30836.00	92508.01
2	504.59%/s	200.44%/s	30864.64	92593.92
3	505.04%/s	200.67%/s	30893.27	92679.82
4	505.48%/s	200.89%/s	30921.91	92765.72
5	522.96%/s	209.63%/s	32048.20	96144.59
6	527.35%/s	211.82%/s	32330.72	96992.17
7	531.91%/s	214.10%/s	32624.70	97874.11
8	536.65%/s	216.47%/s	32930.14	98790.41
9	541.57%/s	218.93%/s	33247.03	99741.08
10	555.56%/s	225.93%/s	34148.06	102444.17
11	562.37%/s	229.33%/s	34587.12	103761.35
12	569.48%/s	232.89%/s	35045.27	105135.80
13	576.89%/s	236.59%/s	35522.51	106567.53
14	584.59%/s	240.44%/s	36018.84	108056.52
15	592.59%/s	244.44%/s	36534.26	109602.78
16	600.89%/s	248.59%/s	37068.77	111206.31
17	609.48%/s	252.89%/s	37622.37	112867.10
18	618.37%/s	257.33%/s	38195.06	114585.17
19	627.56%/s	261.93%/s	38786.84	116360.51
20	637.04%/s	266.67%/s	39397.70	118193.11
21	646.81%/s	271.56%/s	40027.66	120082.98
22	656.89%/s	276.59%/s	40676.71	122030.13
23	667.26%/s	281.78%/s	41344.85	124034.54
24	677.93%/s	287.11%/s	42032.07	126096.22
25	688.89%/s	292.59%/s	42738.39	128215.17
26	700.15%/s	298.22%/s	43463.79	130391.38
27	711.70%/s	304.00%/s	44208.29	132624.87
28	723.56%/s	309.93%/s	44971.88	134915.63
29	735.70%/s	316.00%/s	45754.55	137263.65
30	748.15%/s	322.22%/s	46556.31	139668.94

 Bloody Storm + Upper Stab + Mirror Image + Thorns

Lv	Dagger DPS	Blade DPS	DPS	Mob DPS
1	263.80%/s	209.53%/s	21180.38	160729.38
2	264.03%/s	209.77%/s	21199.05	160878.75
3	264.26%/s	210.00%/s	21217.72	161028.13
4	264.50%/s	210.23%/s	21236.39	161177.51
5	273.64%/s	219.38%/s	21970.83	167052.99
6	275.94%/s	221.67%/s	22155.06	168526.84
7	278.33%/s	224.06%/s	22346.76	170060.44
8	280.81%/s	226.54%/s	22545.93	171653.80
9	283.38%/s	229.12%/s	22752.57	173306.90
10	290.70%/s	236.43%/s	23340.12	178007.29
11	294.26%/s	240.00%/s	23626.42	180297.73
12	297.98%/s	243.72%/s	23925.18	182687.76
13	301.86%/s	247.60%/s	24236.38	185177.37
14	305.89%/s	251.63%/s	24560.03	187766.57
15	310.08%/s	255.81%/s	24896.12	190455.35
16	314.42%/s	260.16%/s	25244.67	193243.71
17	318.91%/s	264.65%/s	25605.66	196131.67
18	323.57%/s	269.30%/s	25979.11	199119.20
19	328.37%/s	274.11%/s	26365.00	202206.32
20	333.33%/s	279.07%/s	26763.33	205393.02
21	338.45%/s	284.19%/s	27174.12	208679.31
22	343.72%/s	289.46%/s	27597.35	212065.18
23	349.15%/s	294.88%/s	28033.04	215550.64
24	354.73%/s	300.47%/s	28481.17	219135.68
25	360.47%/s	306.20%/s	28941.74	222820.31
26	366.36%/s	312.09%/s	29414.77	226604.52
27	372.40%/s	318.14%/s	29900.24	230488.32
28	378.60%/s	324.34%/s	30398.17	234471.70
29	384.96%/s	330.70%/s	30908.54	238554.66
30	391.47%/s	337.21%/s	31431.36	242737.21

I am fairly sure these tables are accurate. What it depicts is the DPS per mob, and DPS over max mobs, using Maxed Upper Stab and Mirror Image, with increasing levels of Thorns. What you can see clearly is that Triple Stab's three hits over Bloody Storms two gives it a significant bonus to its already high Dagger %. In terms of DPS, Bloody Storm requires over five mobs to match Triple Stab's three; however, efficiency in killing mobs should definitely be considered before taking four plus with only Triple Stab.
For comparing damage explicitly, Triple Stab and Bloody Storm are the primary competitors. Flying Assaulter has no where near the DPS output of Bloody Storm, mainly used for rushing and instantaneous damage as opposed to pure damage over time output in my opinion.
Triple Stab, despite being such an early game skill proves to have its own niche in DPS and effective use. For instance, there are situations where Bloody Storm's movement restricts its use where Triple Stab is not only a viable option to attack with, but a great choice for damage.

Owl Dead

 Spoiler

Owl dead is a long-ranged single target attack (300% Range). It has the probability to OHKO a monster as well as a cool down. With a 1410ms Base speed, it is not a particularly fast skill, but it proves its usefulness in its effect.
If your OHKO chance does occur, x amount of your next attack will do 1.5x more damage. In training, this effect provides a significant boost to damage. Presumably it works for each attack, and not each mob, so combining this with mob skills to lower hits to kill on multiple monsters would be more effective in most training situations.
While bossing, this effect will rarely ever occur due to the monster OHKO activation requirement.

Things to further elaborate on or acquire more information about:
Upper Stab + Mob skills.
Damage of Chains of Hell
Final Cut
Stack Effect
Thorns
Advanced Dark Sight