Beyond the 10-mission Campaign, you can test your mettle in Survive or Gun Stand modes.
The starting weapon has been upgraded from a pistol to an Uzi with infinite ammo , and a new radar helps you track down straggling aliens. Performance & System Requirements
The Ultimate Carnage: Is Alien Shooter Revisited Worth the Download?
Compared to the 2003 original, this "Revisited" edition brings several modern touches to the table:
Maps can feature up to 1,000 monsters each, with as many as 100 appearing on your screen simultaneously.
Because it was built on a 2009 engine, this game will run on almost any modern "potato" PC. However, players on very high-end machines should be aware that frame rates exceeding 200 FPS can occasionally cause camera bugs. Alien Shooter Revisited Gameplay - PC