Totenkopf

So far as forms...force form Potency and Affinity seem alright. Was never able to make Mastery work much for me that I noticed, though.

Ataru...I guess it does okay but is fairly isolated in what it does.

Shien...came in handy a few times but TBH you learn it a little late in the game.

Niman...this form is like autopilot, you can switch it on until you meet a specialist of some kind.

Juyo...if you're smart about how you use it you're devastating, otherwise you're just dead. Certainly if you're smart about it, you can use it to kill the bosses rather fast.

Funny, though, for bosses like colonel tobin, soresu is probably best.