Note the environmental textures (walls, floors etc) seen in the screenshots are from the dhtp alterations mod, and are not included here. Taking cues from the infamous Doom comic book, Brutal Doom allows Doomguy to perform all manner of new tricks.
) and pumps new life into the MS-DOS classic.
The end result was Brutal Doom, a mod that takes the original game (or Doom II, or pretty much any IWAD you throw at it note.
Levelling is slower, players and NPCs get less health.
Nevada is a good example of making things more difficult without being openly psychotic.