So I have been marathoning the slayers recently. 26 episodes a day.
Season one is good. Made cheaply, but good.
Season two has a lot of fan service, but it's good too, none the less.
Season three…
Put bluntly, I HATE VALGAAV.
I HATE HIM.
HATE HATE HATE!
He is an unbelievable author's pet, has so much power "Because" to the point where he can beat the slayers+a god dragon+a god+xellos with one hand. He keeps surviving long past when he should be dead, and worst of all, he's an idiotic, self-centred @$$hole whose sole motivation is wanting to destroy the world because his life is unpleasant.
Over the course of the season, he:
•Commits genocide
•If that first one isn't enough for you, then you need counselling
•Is repeatedly a gigantic hypocrite
•Forces one of the characters to do/see things that she doesn't want to, and in an exceptionally rape-y way

All in all, he's the kind of villain who you are highly anticipating the death of. But NOOO, he's a mary-sue, and so he gets reincarnated as a good guy at the end.
GOD, I HATE THAT BASTARD.

Other then that, Season three is a lot of fun.