Half-Life

1ªHalf-Life Serial : 2128-82043-0447
2ªHalf-Life Blue-Shift Serial : 1911-23143-1234
3ªHalf-Life Counter-Strike Serial : 2462-92319-7642
4ªHalf-Life Game Of The Year Serial : 2109-24957-1502
5ªHalf-Life Oposing Force Serial : 2128-82043-0447