So recently, I've seen a number of other blogs post their favorite D&D monsters; guess it's my turn. Below you'll find my 10 most favorite D&D baddies, monsters, and creepies of all time (with links to the appropriate entry in the d20 SRD):
1) Rust Monster: This creature may well be a litmus test for DMs everywhere. I love letting the players know nothing is sacred, and challenging them in different ways than they're used to. Personally, I say don't nerf it; just accept it.
2) Goblins: Monster? Heck, I love them as a PC!
3) Black Dragon: Nasty, vicious, cunning, monstrous bastards without a shred of redeeming qualities. Plus the acid breath seems to always catch my players at the worst time (not that there's a good time for a stream of acid, mind).
4) Troll: He's down. He's back up. He's down. He's back up. He's horribly dismembered. He's back up. Fire. He's down.
5) Bulette: A shark. On land. Landshark. For more on this predator that's only silly when you aren't in it's path, consult Jeff Rients.
6) Gray Elf: I really don't like elves. In my setting, gray elves (or rather, their equivalent), are total d-bags. We've killed more elves in our campaigns than R.A. Salvatore. For this, they make the list as a preferred villian. Wood elves fare much better, but that's a tale for another day.
7) Hill Giants: Because nothing makes your players feel better than taking down a FRIGGIN GIANT.
8) Red Dragon: Sort of the classic dragon, isn't it, with the cone of fire and whatnot? I think they show up as lower/mid-level "boss" villains as much as any other baddie in my games.
9) Gelatinous Cube: One of the best "oh crap" monsters at a DM's disposal during a dungeon delve.
10) Kobolds: Since I prefer goblins more as PCs, kobolds are the best magic missle fodder I have.