Empress set Preparation.

you are going to need all 170 dex in random equips to start it, once you equip parts of the empress set, you can start taking away crap equips, a good idea (if the weapons ever come out) is to get a good top+bottom dex combo, equip everything else, and then your dex should be high enough to allow the overall to be placed.

someone else should be able to tell you the required dex with everything on, but to start, you need a good 170 dex and two slots without equips (where empress stuff will go)

My post puts him @173, with 3 open slots for empress gear.