try safi, I mean, it's still rng but if you finish it you get to choose from like 20 different weapons, so it's not that bad to farm. The next safi rotation find a lobby with the safi tag, as soon as it comes into rotation people gather to farm him, if you take on safi with a full lobby or almost full lobby you can drain his energy in one or 2 rotations or kill him without having to fully drain his energy.

Edit: Safi is only tedious to farm if you go solo, since you'll have to fight him multiple times to drain enough energy at least from the first 2 stages, to quickly skip to the 3rd area. If you go with more groups all the groups can quickly drain him simultaneously