DOOM Eternal - Fortress of DOOM Early Exploration

Very early in DOOM Eternal's development we landed on this idea of the DOOM slayer having a mobile fortress he could deploy from.

Positioned in some point in space it could deploy the Slayer to any location in this dimension, or other, to lay waste to those pesky demons. This eventually evolved into the final Fortress of Doom we have in the game which acts has a hub area for the player. You can see the idea changed around quickly during this process from some sort of military vehicle to a space fairing DOOMslayer temple.

Before it became integrated into the bridge of the final area, briefly there was an idea of having a map room you would enter to go to the levels from.
Early concept of that idea here: https://www.artstation.com/artwork/R3L8QD

Later, and closer to final design for Fortress of DOOM's exterior completed a long time after this previs:
https://www.artstation.com/artwork/68dror

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