What I could see maybe is something like the trinity attack in Type-0. Maybe under certain conditions more than one party member could use LB at the same time. Like if there is more than one gauge filled up. If you can press the LB button quickly enough instead of one level 2 LB, two level 1 LBs are cast, but buff each other somehow, to make them more poewrful than a standard level 2 LB. Or maybe combine the effects and make the level 1 caster LB. hit each mob in the aoe circle with the force of a level 1 melee LB