BLOOM is a 2021 GZDoom crossover project that literally mashes Blood and Doom II together into one campaign. You’ll go through levels that weave locations from both games together in a trippy fashion, fighting enemies that look like stitched together abominations. There’s two different sets of weapons depending on if you choose to play as Doomguy or Caleb.
A fantastic project that deserves all the endorsement I can give it.
Mod link:
https://www.moddb.com/mods/bloom-doomblood-crossover