A couple days ago I was sifting through the mess in my game room when I stumbled across an old players' handout style map.
This map dates back to Dave Dalley's 2nd edition AD&D campaign, circa 1990. Dave was a really great DM when working in small settings and low levels. He could make a game seem epic even when it was just a handful of 3rd level PCs saving the Hammlet of Croak from a demonic cattle rustler. The creature in question turned out to be a berbalang, one of the weird monsters from the 1st edition Fiend Folio.
Fighting this guy on a farm in the dark was quite a kerfuffle. We wounded him and he fled. One of his wings was badly mauled in the initial encounter and he half-flew/half-hopped back to his lair, leaving a trackable trail. The thing's lair was a small dungeon of course. Every monster's lair was a dungeon back then. It's just how we did things. So we crawled our way through some traps and spiders and whatnot. The other players thought we had this guy's number when we caught up with him before he had time to heal. Then the real berbalang showed up.
See, berbalangs (at least in previous editions) had this weird power of projection. It's pretty much like Doctor Strange's astral projection in reverse: the projection hunts for food on the Prime Material plane while the host body chills out on the Astral. So the wounded faux berbalang disappears to be replaced by the fully functional Real Deal. I knew all this was coming, since I had owned the Fiend Folio for years, but I didn't let any word of it slip to my fellow players because I wanted to see their reactions to this turn of events. Some days I can't stop thinking like a DM even when I'm a player.