DOOM (PSX): Demons Infighting
This is a peculiar 'feature', to say the least.
On the PC version, it is impossible to have Demons initiate any sort of infighting due to the way their attack works; they either hit the target or they don't. Other entities in the map can damage them first and cause them to retaliate, but outside of fancy scripting and other non-vanilla methods, you'll never see a Demon accidentally hit something else.
With PSX Doom, this isn't the case. A Demon's attack appears to be a short-range hitscan, similar in behaviour and range to the player's Fist or Chainsaw attacks (it's worth noting that a successful Demon's bite will in fact draw blood from the target, much like either of these attacks). As such it can miss the target completely and hit something else; walls, other Demons, Barrels... you name it.
Of course it's most fun to just watch them start chewing each other apart though. For such a rare event (due to how and where Demons are placed throughout the game), it can be triggered a few times per encounter if you know how to get it working.
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