4.50 Left 4 Dead 2 (2009)
4.32 Half-Life 2: Episode Two (2007)
4.20 Portal (2007)
4.15 Left 4 Dead (2008)
4.08 Half-Life 2: Episode One (2006)
4.02 The Orange Box (2007)
3.94 Half-Life 2 (2004)
3.94 Quake (1998)
3.91 Counter-Strike: Source (2004)
3.82 DOOM 64 (1997)
3.78 Quake III: Arena (2000)
3.56 DOOM (1996)
3.53 Final DOOM (1996)
3.36 Return to Castle Wolfenstein: Operation Resurrection (2003)
2.82 DOOM (1995)
2.58 Quake II (1999)

^*Games must have at least 5 votes to be included.