I feel very accomplished here, as well i discovered a lovely little tactic for fighting him with Onion Knight, equip all the speed and crit bonuses you can, stay in ex mode the whole fight, and use Gliding swipe over and over, "heres where i found an intresting thing," when chaos is below you after you hit with the Square finisher he charges you, during his charge if you master the timing with "O" you begin your combo on him unblockably and can simply continue this tactic till he dies.

for whatever reason he glitches and only charges you over and over and over. i never even had to use an EXburst when i discovered this!!! :D

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