DOOM 64's demons breach the Facility mid-round. Grab the shotgun, chaingun or plasma gun that drops, and survive the vents.
How to join The host starts a game from the game's own multiplayer menu, and friends join that game from theirs, or through the host's invite. Everyone playing needs this mashup from Melty.
A normal round of LOCKDOWN Protocol... until the alarm goes off. Every couple of minutes, DOOM 64's demons pour out of a random wall vent and hunt down everyone in the Facility, employees and dissidents alike.
What you get
Controls: left click (or right trigger) fires the DOOM gun you picked up. G puts it away or takes it out again.
Everything from DOOM 64 comes from your own copy. The first time you play, the mashup reads your DOOM 64's sprites, sounds and music and prepares them, which takes about a minute in the lobby. UE4SS comes with the mashup.
You need LOCKDOWN Protocol and DOOM 64 (Steam).
Known limits: joining a friend's lobby with the mashup hasn't been tested between two real Steam accounts yet. Demons only walk the Facility's ground floor and pass through doors.
Not affiliated with id Software, Nightdive Studios, Bethesda or the makers of LOCKDOWN Protocol.