Because of the enormity of the series, this ranking will focus on the mainline entries and its console-exclusive shooters. This excludes quite a few portable and mobile games, including what is undoubtedly the worst sequel in franchise history. Released on the PlayStation Vita, Call of Duty: Black Ops: Declassified is leagues below anything else bearing the CoD branding thanks to its laughably short campaign and shoddy multiplayer offerings. On the flip side, several Call of Duty ports to the Nintendo DS showed impressive-at-the-time graphics and controls for the handheld.

Related: Call Of Duty: Which MW2 Is Actually Better

One thing is clear when looking at the franchise's history. As long as a game feels like Call of Duty, fans are willing to run with just about everything. From the great global wars to modern conflicts, from multiplayer arenas to bombastic campaigns and the realms of the undead, here is a tour of duty through Call of Duty's history.

#22 - Call of Duty: World at War – Final Fronts

Developed on the PlayStation 2 alongside Treyarch's last trip to World War 2, World at War – Final Fronts is a PlayStation 2 exclusive campaign developed by Rebellion. The team has thrived in the setting before with their own Sniper Elite series, but the AI issues and lack of multiplayer make this odd Call of Duty footnote well worth skipping.

#21 - Call of Duty: Finest Hour

Another console-exclusive entry in the time when current consoles couldn't run the same Call of Duty games as PCs, Finest Hour provided a sneak peek at the franchise to players on GameCube, Xbox, and PlayStation 2. Featuring online multiplayer and some exclusive modes, it was a fine entry for its day but clearly hampered by its status as a spin-off.

#20 - Call of Duty 2: Big Red One

The last of the console-exclusive spinoffs, Call of Duty 2: Big Red One is the first Call of Duty game helmed by Black Ops creators Treyarch. The campaign follows a specific squadron of soldiers in World War 2 and features unique documentary-style presentation thanks to footage provided by The Military Channel and narration by noted voice actor Mark Hamill.

#19 - Call of Duty: Ghosts

One of the few singular entries in the mainline Call of Duty series, Call of Duty: Ghosts proved to be a false start for developer Infinity Ward as they tried to start something new after Modern Warfare's grand finale.

Related: Call of Duty Ghost Actor Fired After "Misogynistic, Harassing" Comments

While critics at the time praised the game's unique player vs. aliens mode and its multiplayer additions, the campaign fell far short of normal expectations.

#18 - Call of Duty: WWII

Call of Duty: WWII is a fine return to the roots of the series, but it does not strive much beyond that. With gameplay and a story that hits similar notes as the original Call of Duty and its two direct sequels, WWII only serves to prove why many franchises abandoned the fight against Nazis after so many repetitive years.

#17 - Call of Duty: Infinite Warfare

Introducing spaceships and a war for the solar system, Call of Duty: Infinite Warfare takes the series into the farthest tomorrow yet seen. Infinity Ward's take on a futuristic Call of Duty fell flat with many fans who wanted more grounded and modern combat, but the meaty campaign and futuristic weapons did find their own fans in the end.

#16 - Call of Duty: Black Ops III

The third Black Ops game stretches the conspiracy theory-laden plot to the absolute maximum in a future filled with augmented super soldiers and optional zombie infestations.

Related: Modern Warfare 2 Leak Hints At Two Fan-Favorite Call of Duty Maps

While Call of Duty: Black Ops III is one of the most feature-packed entries in the Call of Duty franchise, it also felt like a stopgap in both the progress of the main series and the Black Ops games.

#15 - Call of Duty: Black Ops Cold War

This latest entry in the Black Ops series feels just as perfunctory as Black Ops III, and for good reason. With more and more focus going into the franchise-spanning Warzone, the standalone aspects of Cold War feel like side features to an ongoing service game. Add in the controversies generated by focusing on the Regan-era of politics and the whole game feels like it may be one of the less-ed entries in Call of Duty history despite its record-breaking sales numbers.

#14 - Call of Duty 3

Treyarch's first mainline entry in the Call of Duty franchise (and the only mainline entry not released on PC) feels like a testing ground for what was to come in their Black Ops games. The campaign is similar in scope to other console-exclusive spinoffs and the multiplayer feels like a small iteration on the first two games in the series. Call of Duty 3 is on the cusp of greatness, but that would come later.

#13 - Call of Duty: Vanguard

It was rare to see a Call of Duty launch with a whimper rather than a thud, but Vanguard arrived amidst a company-wide controversy at Activision. The game finds itself described as a stopgap entry in the franchise more than once in reviews, with complaints also hitting on a brief, lackluster campaign. While there are some innovations in the Zombies offering that make it slightly better than 2020's game, the multiplayer is a known quantity that suffers the same shrouded fate as anything released with Black Ops Cold War.