Mini Doom

Description
Mini Doom is a short Doom fangame, with the shareware episode of the original Doom reimagined as a 2D platform shooter. Gameplay is quite similar to Doom but on a 2D plane. Find keys to unlock doors, collect familiar weapons and power-ups, blast demons and locate secret areas. Most of the enemies, weapons and power-ups from the original Doom make an appearance, though some function quite differently.
Dying will send you back to the start of the level you are on, but you get to keep the keys and weapons you have collected.
There are two difficulty levels to choose from.