Probably the most rediculous fight I've had so far in 4e was against a NPC the DM cooked up.
All the NPC had on her (we'd searched her earlier in the session) was her normal clothing, a cloak and a dagger to protect herself. She attempts to stab another NPC we have with us, fails, then teleports away.
We all assume that she fled when the ENTIRE PARTY came out of a cave to stop her. But sure enough, next turn she fires a necrotic spell at us and disappears again. After about 20 more rounds of this (her popping up in different areas all over the place) we finally succeed in killing her. We search her again, because we're thinking she had to have some sort of magical equipment.
Turns out all she had was a Pact Blade and a Cloak of Elves, which gave her a bonus on her Stealth check. She did know the Teleport spell and she recharged it several times, but all she did was Stealth and we'd fail our Perception checks by like 1 or 2 everytime, and we weren't rolling bad either, it was just that the bonus she got from the cloak was just enough ot make her go from "stupid NPC" to "annoying bitch NPC."
Oh, and the DM having to house rule in what happened when a creature got Tide of Iron'ed into a Flaming Sphere was also hilarous. He decided that the sphere would get another attack at it. So whenever the Wizard cast the Flaming Sphere, I ran up and Tide of iron'ed it into the sphere and roasted them
