"A Wight." Makes me laugh.
In my last 2E campaign, the party (on a random overland encounter) braved a single room barrow and were ambushed by 16 Wights. Yes, you counted that right. Rolled it straight out of the MM. They were a pretty powerful party, but no less than 3/8 party members lost levels, some of them more than one before they won the battle.
Took 'em a while to get those levels back- two full modules worth of adventuring IIRC. That was a lot of XP that had to be re-earned. Watching them s--t their pants when 16 wights jumped them was something else. They were lucky to survive- I was thinking it might be a TPK, but we let the dice fall where they may, and they survived.
And it was FUN!