The action-RPG modification Modular Combat has released version 1.50 and the 1.51 patch that addresses a few bugs. You kill to gain experience and purchase upgrades (modules) to your HEV suit. Some of the changes are as follows:

Modular Combat 1.51

Episode II is not a requirement!

New monster: Antlion Worker

Votable gamemodes

Particle effects are back! The game looks better than ever!

Improved the module usage system...you can now tell if a module is recharging

Revamped whole AI system! We now have on-the-fly control over how easy or hard our monsters are....and we are giving that control to you, the players, as well!

Added tons of CVars to give server admins control over their abilities!

For downloads and more information, be sure to check out the ModDB profile and the official wiki.