Fasalla's Guile is an Elite Gear Set. Set pieces can be bought directly from the Elite Gear Vendors using Alliance Points, and are also available via "Rewards for the Worthy" mails by participating in PvP. Pieces are Abah's Watch Style in Heavy Armor.
2 items: Adds 28-1206 Maximum Health
3 items: Adds 28-1206 Maximum Health
4 items: Adds 4% Healing Taken
5 items: You apply Minor Defile to any enemy that comes within 5 meters of you for 2 seconds, reducing their healing received and Health Recovery by 15%.
The set consists of heavy armor and jewelry in all slots, as well as weapons and shields of all types.