Found out awhile back that the full Cow King set turns your character into a cow. It's not a very useful set for endgame without some seriously lucky corruptions and upping it, but it's fun to throw on a character (or a merc) for laughs. Tried it on my Blade Fury sin the other day and realized the blade sprites are invisible, so I was basically glaring at things and killing them.
Any other sets change characters' appearances? Assuming full Trang still turns you into one of those A3 ghouls, there's two that I know of. Would be cool if say, having the full Gris set turned palys into Griswold or something.