Location Fallen Sun 2 Set Effect  +15% HP
4 Set Effect Effective exclusively.  Increases the Effect RES and damage of all allies by 15% (doubled for the equipped unit) at the end of a turn if the equipped unit launched a normal attack or was unable to take actions in the turn.  Sustainable for 2 turns.
Suggested Use Great on supports that have skills that last multiple turns allowing them to attack inbetween (Kaguya, Shiranui, SP Shuten,  Haku Shoujo, Kingyo, Ebisu, Otakemaru, etc…)
Note Usually for more offensive teams to deal more damage in the beginning of the fight