Each point is one game's rating·dashed lines show each series' overall trend
Games on the chart (6)
| Half-Life | Nov 19, 1998 | Main Game | 80 | 88 | 84 |
 Half-Life: Uplink | Feb 12, 1999 | Main Game | – | 79 | 79 |
| Half-Life 2 | Nov 16, 2004 | Main Game | 79 | 90 | 85 |
 Half-Life 2: Deathmatch | Nov 30, 2004 | Main Game | – | 75 | 75 |
 Half-Life 2: Lost Coast | Oct 27, 2005 | Main Game | – | 67 | 67 |
 Half-Life: Alyx | Mar 23, 2020 | Main Game | 93 | 93 | 93 |