Sega's Aliens Vs. Predator has topped Steam's weekly sales chart for the past seven days.
The Sega title - developed by UK studio Rebellion - outperformed the likes of EA's Battlefield: Bad Company 2 and Activision's Modern Warfare 2 in the week.
Counter-Strike: Source kept the end up for the golden oldies, grabbing 10th spot in the list.
The full list reads:
1. Aliens vs Predator
2. Battlefield: Bad Company 2 Limited Edition
3. Call of Duty: Modern Warfare 2
4. THQ Complete Pack
5. BioShock 2
6. Warhammer 40,000: Dawn of War 2 Chaos Rising
7. Mass Effect 2
8. Left 4 Dead 2
9. Global Agenda
10. Counter-Strike: Source