I just got my Kannagi, after reading few pages, got an idea on my gear, and made some testing inside aby.

First on the Manticores, then tried and solo'd the NM, had to use temps coz Stonega IV and Stoneja.
As Atmas uses Apoc, GH, RR, no food.
This is my set, that will try to improve eventually.
Seiryu's Kote Crit Hit +3, STP+4
Byakko's Aug, Agi+3 Stp+4 Crit Damage +4
Any suggestion will be appreciated. (Still dont have any Neo Nyzul Gear... )