Is co-op possible? As shown with the bot mods, you can have bots in a multiplayer game. And as shown with the library map, you can make singleplayer maps multiplayer. Couldn't you combine these two? Can you make triggers in multiplayer? Shouldn't you be able to make a co-op game? You could make the game type slayer (and just hope the players don't TK eachother

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The only level I don't think you could do is the Pillar of Autmn (and you could just skip the bigenning part anyways)