I've never played Doom but who does not know Doom by other games, it really created the fps; you in the other hand, I think you played Doom, the original, and you are know presenting you vision of Doom the thing which is very nice. First I wanna ask: Is the goal of the game to survive as longer as you can? And know lets do the same kind of review you do to be organized:
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Things I enjoyed:
-The smooth camera, it is not too obvious how to make it as perfect, too much developpers get stuck at that.
-The atmosphere of the hell which is ponctuated by small details like the smooth and red sky that I loved too much
-The assets that seem handmade
-The well choose of the music and the good sound design
-The fact that both weapons, the shotgun and the gun, are fun and give satisfaction while shooting
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Things that need improvement (or things i didn't like as other things):
-Graphics of ennemy? But it's a question of style
-Respawn, you should make enemies inactive for at least two seconds
-It's only one wave in the game I would prefered levels
- more types of ennemies, but okey that was a jam
-The thing that the theme isn't present. The rewind mechanic isn't that impressive or different from actual respawn
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Really good job, I really felt playing in an actual game not made only for a jam! Continue like that, I'm looking forward for a final version of this; Valar Dohaeris!