Thread:Linathan/@comment-26231443-20180722112031/@comment-26140304-20180722195512

Arumat's SBB recast buff (if you take the SP option) does stack with Elaina's UBB recast buff, which would result in a 100% chance of recast due to recast buffs stacking additively as opposed to individual stacking for other probability buffs.

As for Arumat's ES, the damage taken increase passive affects the entire squad, regardless if Arumat is equipped with an Atk-Boosting sphere or not.