

The mod focuses on multiplayer, but you can fight the AI as well as play single-player missions. Each faction has its own units, abilities, buildings, research and defences. In Lambda Wars you play as a commander of the Resistance or an overlord of the Combine. It's a standalone mod, so you do not need Half-Life 2, Alien Swarm or any other game built on Valve's Source engine to play. Lambda Wars, a mod for Valve's 2010 top-down shooter Alien Swarm, passed Valve's Greenlight process in January and has now launched as a free download on Steam.

A mod that turns one of Valve's games into a real-time strategy set in the Half-Life 2 universe has been released on Steam after six years of development.
