loganw234/mercenaries2

Merc2Reborn is a revival project for Mercenaries 2: World in Flames, a 2008 action game by Pandemic Studios whose official online servers were permanently shut down by EA. The project has two main goals: restoring the multiplayer matchmaking service so the game's online mode works again, and exposing the game's internal Lua scripting engine so modders can run code against the live game. The multiplayer restoration works by intercepting the game's network traffic at the Windows API level. DNS calls that would normally go to EA and GameSpy servers are redirected to a replacement server emulator. Certificate trust checks are bypassed so the replacement server's self-signed certificate gets accepted. The system clock is also spoofed to a 2012 date to fall within the original certificates' validity window. A public community server at refesl.live already handles matchmaking for anyone who installs the client-side fix, so most users do not need to run their own server. Running your own FESL server is described as non-trivial because the original game's handshake requires SSLv3 with the RC4 cipher, both removed from modern operating systems due to known security weaknesses. The Lua bridge works by loading an ASI plugin into the game process through a tool called dxwrapper. The plugin hooks into the game's Lua interpreter and starts a local TCP server on port 27050. You can connect a Python REPL tool to this server and send Lua commands directly to the running game, including calling internal functions the developers left in the binary, such as a developer cheat menu. The codebase is described honestly as iterative reverse-engineering rather than polished software, with leftover experiments and workarounds that have not been cleaned up. Active mod development has moved to separate repositories linked in the README. Phase 3, mapping the full engine API and building mod tooling, is still in progress. Building requires Visual Studio 2022, a retail copy of the game, and dxwrapper.