2-3 player co-op New Vegas: shared fights and story, revives, trading, plus sprint, Titan power armor and time stop.
Play Fallout: New Vegas with 1-2 friends. Each of you brings your own Courier and save; joiners appear beside the host and fight the same Mojave.
Every setting and key bind is in Documents\My Games\FalloutNV\MojaveCoop.ini (F7 in game shows it); changes apply live.
Known limits in 0.1.0: teammates have a preset face (race, hair, armor and weapon match); enemies spawned during play aren't shared; a traded weapon arrives in fresh condition without mods; the quick-loot window is still experimental and off.
Included (open source, under their own licenses, built from their public source): New Vegas Tick Fix by carxt, Tgspy, lStewieAl and WallSoGB (LGPL-2.1); Mod Limit Fix by iranrmrf (GPL-3.0). Sources and licenses are in the download.
Recreated from scratch, with thanks for the ideas: Quantum Trigger by Hopper31, Automatic Riot Shotgun by Stonedturtle26, Loot Menu for FNV by Gribbleshnibit8, Titans of the New West and Enhanced Movement by Wombat. None of their files are included. Built on xNVSE by the NVSE/xNVSE teams; engine layouts learned from JIP LN NVSE (jazzisparis, LuthienAnarion).
Fallout and Fallout: New Vegas are trademarks of ZeniMax Media / Bethesda Softworks; this mod isn't made or endorsed by them. JoJo's Bizarre Adventure belongs to Hirohiko Araki / Shueisha: no JoJo audio is included. The optional TimeStopSound setting only plays a sound file you supply yourself. The mods credited above belong to their authors, who don't endorse this project. Free and non-commercial; back up your saves.