Uni-the-Unicorn!
Hero
There others to IIRC, but it is rare. Probably best for most people/groups to play with it being rare. Of course we play death at 0 period, so no big deal for us!That's around. There's a monster in Spelljammer that has a brain extraction attack, if it takes a PC to 0 hp with it, that PC dies and their brain gets extracted. No save. Party got unlucky and I landed it on the Rogue. While running Light Of Xaryxis.