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gm_flatgrass_arena

A large arena consisting of blue and red teams. Use for multiplayer or singleplayer. Be sure to disable noclip/god/phsygun for full experience. There is a little secret too, but it needs portal gun to access. Don't let anyone outside the walls (except if they find the secret or they don't want to play).
The ammo packs are not decoration, use them! Have fun :D