Against Ditto-Arceus.
I'd prepped a baton pass + double team Ninjask just to outspeed it and kill it with one of my better mons.
Yet, my Ninjask got ko'd, and I thought I'd have to redo the battle...
I could've soft resetted, but I went on just for fun.
Turns out when my last pokemon, my dear Florges, went on battle, Ditto-Arceus missed Judgement like 2-3 times in a row!
So I won with Mistry Terrain + two Moonblasts.
Talk about getting lucky hahaha