Several Doom 3 monsters were cut in the design process and did not make it into the finished game. Various concept designs of these monsters were shown amongst the pre-release Doom 3 promo material. One of them was a new version of the Arachnotron and Spider Mastermind while the rest were apparently new designs. Eventually some of the unfinished monsters were finished and used in the Doom 3 expansion, Resurrection of Evil.
Images
An Arachnotron model that was cut from the game. The Spider Mastermind uses this model but both of them got cut.
An early Hell Knight model.
Another early Hell Knight which looks like a Gremlin.
early zombie or revenant
early sarge model
early sarge model "human form"
early sarge model "zombified form"
early uac marine. This version is unused in Doom 3 but is used in the ios handheld Doom resurrection
A conceptual idea for a Z-Sec.
A concept art drawing of the Marine.
A high-resolution render of the different Zombie's heads.
A cut model for the Demon.
unused character
A demon that was cut from Resurrection of Evil.
A possible cut Bruiser model.
Early Lost Soul/Forgotten One concept drawings.
Another skin for the early Demon.
Early concept art for the Demon.
The skeletal system of the early Demon.
The Hell Knight's final model.
An early idea for what the Zombie's disfigurations should look like.
An Spider Mastermind cut from Doom 3 seen on a wall in Rage.