I'm saving up pulls for the next phase. For those of us without any full break, part 2 of the tactics event in a few days is a godsend. All 3 banner units are break users.
Ramza's the 5*-6* unit, so super rare, but he has -40% breaks that last for 5 turns (superior to fullbreak's -30% for 3 turns), although they're split into 2 debuffs (str/mag, def/spi). It will take him two turns to fully break all stats, but then his breaks are the best in game (currently), so he's the best support for a hard multi-turn boss battle.
Agrias is 4*-5*, so still rare'ish, but she has fullbreak, and both an 140% aoe (blitz) and a 300% single target hit (cleansing strike). Nothing too special, but it's just another fullbreak user.
Mustadio is the consolation prize, as a 3* base he will be very common from the banner. Still, if you don't have fullbreak, he at least provides the -30% debuff, though like Ramza, his is split into two different skills, so he takes two turns to get all debuffs up.
I'm going to pull until I get at least one of them, since I have no fullbreak potency debuffs at all on my roster.