Best mob for attendance event.

I disagree about the garden. Its only good if you can travel the map fast (or 1hko them). My Mercedes does fine rushing them all, but my AB does it much faster at ToT (since she 1hkos tot and 1hkos garden). Oblivion 4-5 are good.

Tbh for me the most important parameter is accessibility. I don't have a hyper rock so I like that I can just get to Root Abyss from anywhere. So some classes can kill faster at ToT I'm sure, but for people like me, you would save time by going to RA if you don't happen to be in ToT/Leafre* already.

(*I hate Leafre and it's god-awful BGM; I avoid it like the plague)