“Plaguespreader” Fallen Takumi build

The set does look fun indeed, but it's quite risky. Having 20/19 Def/Res he probably is going to tank one Physical/Magical hit. Also, due to the restrictions of Windsweep allowing the skill wielder to only Attack once in combat is also risky. This all can be countered if you have another ally to take out the foe that F!Takumi is taking out.

I use Fury and Poison Strike in the B slot. Also, Savage Blow SS > Poison Strike SS.

Basically, Desperation in the B-slot would probably best. If you can boost his speed with a tactic, you reach 47 speed. Enough to double most things.