H2H-Xmas.wad is a Christmas themed 32-level pwad for Doom 2. From the txt file:
In a brash move… demons for hell attack santa’s factories at the north pole taking Santa and several hunder elves hostage. The Space Marines dispatch DOOMGUY to clean up the mess. After a bloody fight in the monster puzzle room, DOOMGUY is able to close the gate to Hell and save christmas. Thus ended XMASDOOM… or so we thought.