The latest annual update to America’s favorite murder simulator presents many enemies to the player: Tropas in Cuba, Vietcongs in Vietnam and Russians in the Arctic. But Treyarch, which previously developed “Call of Duty: World at War,” remain the greatest enemy of all. After playing through a campaign filled with unreliable team AI, getting stuck because of misdirection and facing endless swarms of Vietnamese troops that don’t stop until you perform a non-indicated action, it will be Treyarch’s name that you curse above all others.

Most of the 5.6 million copies sold on the game’s release date were likely purchased for multiplayer: Treyach’s strength. This year’s new features and maps are welcome additions to one of the best online shooters available. The perks and personalization of “Modern Warfare 2” are faithfully implemented along with a new leveling system that lets players earn points from matches that can be spent on new gear and perks. These points can also be gambled in new game types, including one where players start with only a knife and a pistol with one bullet. Zombie mode from “World at War” also returns with minor improvements.

The single-player mode is where the game falls short. It’s the most ambitious campaign yet, packed full of set piece moments every five minutes. Some players will get a thrill out of the rollercoaster pacing and constant interruptions, but I personally found these scenarios — along with sawing through the necks of unaware Vietnamese soldiers while a squad mate cheers, “Never gets old” — to be a trying attempt at creating shock value where a better designed series once stood. The good news is that most of what you like about the series remains. The bad news is that you probably own those parts already.

Grade: B
For fans of: “Apocalypse Now,” Alex Jones and presidents killing zombies.

Medal of Honor (PC, PS3, Xbox 360)

There’s an irony that comes with the release of “Medal of Honor’s” 2010 reboot. The franchise responsible for creating the World War II console shooter that led to genre fatigue has now returned in the form of a modern military shooter in a year that is full of them. Thankfully, there are novel ideas, gorgeous visuals and a unique aesthetic to set it apart from
the competition.

In what was a terrible decision from the start, the game’s two components are developed by separate teams. DICE handled the multiplayer, essentially stripping away the best features of their “Battlefield: Bad Company 2” without adding the ideas that stand out from the single-player campaign, developed by Danger Close.

There is a grounded realism to “Medal of Honor” that is at times fascinating in concept but too often boring in execution. Being able to slide to cover, peek around corners and pull out a pistol with the double tap of a button are all great additions (none of which appear in multiplayer), but they can’t prevent the game from feeling like an endless shooting gallery from an earlier age.

Grade: C

For fans of: “Call of Duty 4: Modern Warfare,” ATVs and gnarly beards.