This is a list of mods that add multiplayer support to games that were officially released as singleplayer only.
Qualifying entries include ... + Mods that expand existing multiplayer modes, e.g. turning a 2-player game into a 3-player game. + Mods or tools that restore multiplayer modes in games with closed servers or outdated netcode. + Useful tools that aid in expanding multiplayer connectivity, such as adding remote play to local-only games. + Ports or remakes that add new multiplayer modes, such as making a game into an MMO.