If you are doing lan-parties , this opensource AAA Game is the best . https://totemarts.games/games/renegade-x/ It is Command and Conquer Renegade , RTS + FPS Game with frontend backend opensourced rebuild from scratch in Unreal 3 . Needs a lot of teamwork and strategy to win and all gameplay is according to CNC Rules.

https://www.youtube.com/watch?v=_VHennwBhG8

Source code

https://github.com/TotemArts/Renegade-X https://totemarts.games/forums/files/file/7-renegade-x-softw...

Game Client

https://totemarts.games/games/renegade-x/downloads.html

They have a New game working in Unreal 4 Which have full build building and production RTS mechanic.

https://www.youtube.com/watch?v=HhzZ3GMerz4

They would use some help from you guys to spread around, they are fully self funded and voulenteers working full time , to build a game that is fun for hardcore playerbase.