Kacchuu Musha

That thing has 78mil hp, it would take ages to kill for lvl 120 no? Papu has over 3 times less hp and gives same EXP... I never found 1 anyways(even at Yellonde).

But if it takes like 1-2hours to kill, 15% is not worth it for 12X.

That depends on funding, really. My Hero in Zenith obviously can't kill Musha within a decent time frame, because my Hero only deals 15k ~ 30k damage per Brave Slash. However, people who are pretty well funded can kill it pretty fast if they're doing 50k ~ 100k damage per hit. I've seen some people who, at level 100, put my level 161 Viper's damage to shame.