Fast monsters

Fast monsters is a setting which mades the enemies move and attack faster.

Demons and Spectres move and attack 2 × faster, Imp fireballs are 50% faster, and Cacodemon, Hell Knight, and Baron of Hell projectiles are 33% faster. Consequently, lesser enemies are considerably more dangerous, and the chainsaw is virtually useless.

Fast monsters show up by default only on Nightmare mode. This modifier can be used with any skill level using the -fast command line parameter. Doom Legacy has a game launcher which allows the player to choose the fast monsters option with any skill level.