Kingdom Hearts III - Skoll No Damage (Better) (LV1 Critical Mode)
This was the only fight I used Elixirs and a Hi Refocuser, so I wanted to redo it without rare items.
This boss is the worst in the game among the heartless bosses (even though a couple Keyblade Graveyard fights are more BS). You can sort of loop him when he summons the tiny wolves, but it can break easily, if a party member attacks (you should set them on Sora attack), or if a tiny wolf messed your timing.
I ended up letting him do both DMs just in case. I still had to use Simba to get rid of the tiny wolves (especially during the DM), I don't see any other reasonable way to do it that doesn't involve luck in some way.