TA Spring is an open source project aiming to create a new RTS (realtime strategy) game. By default there is XTA mod known from Total Annihilation to get something to play with. Plus You can play additional mods like Absolute Annihilation, UberHack, etc. It reads original TA unit formats directly without conversions needed, so 3rd party units work just as well as the original ones. Maps from original TA are not supported.