I made a villain probably more than 15 years ago at this point that, to this day, any player who was in that campaign will promptly tell me "fuck you" if I mention him or do a little flourish with my finger.

Philip the Brigand! He was born of several suggestions for memorability. A title, not just a name. Personality flair (such as, but not limited to, the flourish), and a knack for escape being the three I remember. Not plot armor, for sure. A great eye for knowing when the battle wasn't going his way though, which was usually shortly after ruining the party's day. Like when he loosed a rust monster that destroyed the fighter's treasured sword and also broke the monk's arm.

Mostly they pictured an incredibly annoying version of Autolycus from Xena/Hercules. Not unfair.