Onion Knight's Mace of Zeus [USSB, +10 MAG] - MAG/MND/RES +30%, Quick Magic 3 & Haste to party, EX "Sage" to user EX "Sage": MAG +30% & BLK Damage +15%
Onion Knight's Onion Blade [USSB, +10 ATK] - ATK +50%, Critical = 50% & Haste to party, EX "Ninja" to user EX "Ninja": ATK +30% & Casting Speed increases per action (up to 8 stacks: 1.0 > 1.3 > 1.6 > 1.9 > 2.2 > 2.5 > 2.8 > 3.0x)
He's a speedrunner's top choice, along with being the only character so far that has a doublecast black magic record materia (so he can doublecast flare) Mages are making a scary comeback with him and Ashe/Rinoa/Krile chase USBs.
So that is amazing, and it would seem to make make Migicite a lot easier for mages especially.
But I just don't see any situation that that is better than Tyro's God Wall unless you are a speed runner and decided defense doesn't matter to me anyway.