Recently, modder rayjiun released a trailer for a massive map for the zombie mode in Call of Duty: Black Ops 3.
The "Machin[A]" project combines elements from various franchises - players have noted elements from Helldivers, DOOM, Resident Evil, Wolfenstein, and Lies of P.
The use of assets from other projects was intended, such is the concept of the map - a gradual increase in the absurdity of what is happening.
"Machin[A]" should soon be presented in open access, and early access may be granted to those who supported the developer through Patreon.