Not mine, but I remember an old d&d quip, maybe from tumblr: Door mat at the dungeon entrance with a sign that says 'please wipe your feet', door mat is a rug of smothering that attacks anyone who doesn't >:)

Similar happened in the CoS game I'm in. 6 person party, my Druid carrying half the encounters while the Rogue is chronically unconcious. Until I get my ass kicked by a broom that none of the party could hit and the rogue just waltzes in from the other room and one-shots it lol

I've fought these twice. One of them full on killed our cleric.