Halo Maps.org is and easy way to source comunity made Halo Custom Edition maps. As well as having the download for the game itself, Halo maps also has areas for halo 2 vista, portal maps, a forum, an area for art, and a machinima section, containing in game and scripted machinima. It now also contains a sub-section inside haloce maps for multiplayer maps with ally and enemy AI in them, so that you can essential play firefight on the pc. Link to website-http://halomaps.org/.