@shavecat When you enable the port 1 multitap, you have to restart the emulator to have it take effect. Probably the best thing to do is to save a game options file with multitap mode set to "port 1 only" so that that particular game always loads with the multitap on.

This is in Quick Menu -> Options -> Manage Core Options

Try deleting the game options file if there's already one there.

So, to summarize:

Start your game Go into the RetroArch menu's Quick Menu -> Options -> Manage Core Options Delete the game options file, if there is already one Go back to Quick Menu -> Options Set Multitap mode to "Enable on Port 1 Only" I also Disabled "Force Analog Mode on Restart" for both player 1 and player 2 (not sure if this matters; I just wanted to avoid the pop-up message when the game loaded) Go to Manage Core Options again and save the game options file Exit the emulator as you usually would (Select + Start?) Re-enter the game

Note that the Twisted Metal games only allow more than 2 players in deathmatch mode. Tournament mode is limited to 2 players max. Let me know if you have any issues.