Halo 3 Project Reclaimer is a free PC build of Halo 3 that sits on your Master Chief Collection files and then ignores the old player caps. Campaign co-op goes to 16. Custom games, as of the 0.9.0 release, go to 64. You can host the lobby yourself, or point people at a dedicated server. You need a copy of MCC. The project uses those files, including Steam Workshop mods, and the install notes say you can clone the Halo 3 campaign and multiplayer files into a local version.
Sixteen people in the Halo 3 campaign is the number that makes the rest of the feature list feel small. Vanilla co-op was four. Reclaimer lobbies take six, eight, ten, twelve, or the full 16, and a single PC can still do four-way split screen on top of that. The host picks the mission, the start point, and the difficulty, then starts it for the room. Checkpoints can be rolled back for everyone. Finish a mission and the next one starts for the whole lobby. It does not touch multiplayer rank.
Who you are in that mission is a choice now. The default is still Master Chief and the Arbiter. A characters toggle lets the lobby play as the Spartan or Elite they built in the customize screen, armor and emblem included. Cutscenes still show the Chief. A room can also just be sixteen Chiefs, or sixteen Arbiters. The campaign gets easy when that many guns are in Sierra 117. That is the trade.
Customization is the other half of why people are installing it. Helmet, left and right shoulders, chest. Primary, secondary, and detail colors are no longer stuck to Halo 3's thirty presets. The panel can switch from the palette to a custom field: hue, saturation, brightness, or a hex code. A bright green Spartan is allowed. Other players see the custom color in game, on the lobby card, and on the scoreboard if they and the host are on a recent build. Older clients fall back to the nearest official color. Frame rate goes up to 240. Played back to back with the 2007 game, it is the same campaign at a frame rate that game never had.
Networking got a pass with it. Old Halo 3 co-op was the version where one bad ping dragged the whole session. Hosting your own server is the point of the project, and dedicated boxes are already up. Custom games hold 64, a dedicated server holds 63 and still defaults to 16, and the scoreboard and carnage report list everyone. Campaign stays at 16 no matter what the server cap says. Everyone in a match needs the same version. Controller aim can be MCC's modern diagonals or Halo 3's original response. Team changing can be off, on, or balancing-only, including mid-match.
Halo 3's code has been decompiled, which is why this exists. Halo: Combat Evolved's decompile already produced 128-player servers, including a Blood Gulch lobby in the 70s with no bots. Reclaimer is not that lobby yet. The current public cap is 64 in multiplayer. A 128 Halo 3 room is the number people are watching for, not the number you can queue tonight.
The practical version is simpler. Own MCC. Install Reclaimer. Host a campaign. Bring more than three friends. Paint the armor whatever hex you want. The 2007 mission still ends the same way. It just does not care that Bungie thought four was enough.
Are you loading Sierra 117 with a full 16, or jumping straight into a 64-player custom? Let us know your thoughts in the comments below.