All month long, we're covering Call of Duty: Ghosts in conjunction with our October cover story. When it releases in November, it will mark the tenth release in the core series. Throughout all of those games, Infinity Ward and Treyarch have managed to maintain a steady bar of quality that rarely dropped. It's not the easiest franchise in the world to rank because of this, but we're going to try anyway. Read on to see where we placed each of the previous nine Call of Duty games.

9. Call of Duty 3

The lowest point in the franchise came with its third entry in 2006. While it was still a solid game, its globetrotting World War II campaign began to feel repetitive after the two similar entries that preceded it. Awkward quick-time events during scripted melee segments didn't help, either.

8. Call of Duty: World At War

If World War II felt tired by the time Call of Duty 3 came along, it was disappointing to return to the same era after the amazing Call of Duty 4: Modern Warfare. On the plus side, Treyarch's campaign was better than their previous effort, and this entry marked the first appearance of the popular Zombies mode.

7. Call of Duty 2

When the Xbox 360 launched in 2005, Call of Duty 2 was many gamers' go-to launch title. Its multiplayer seems basic by the standards set in later entries, but it was a blast in the early days of the new console. Impressive smoke effects and overall visual quality were also a nice reminder that we were about to embark on a new generation of console gaming.