The Gears of War series owes a lot of its longevity to its multiplayer community, which stays active enough to earn its sometimes comically labor-intensive Achievements. So it's no wonder that the team at Epic has learned to listen to its most devoted players. Gears of War: Judgment is introducing two new multiplayer modes that not only tie directly back to the community, but that freshen up the formula in some major ways.

The first new mode, OverRun, owes its existence to both Horde and Beast modes. The two had always been inverted twins, so pairing them together only makes sense. But to match the Locusts' natural inclination towards different combat roles, Epic and People Can Fly have introduced a class system for the COG (human) players as well. Humans only have one tier of classes, and can't upgrade to stronger units like the Locusts, but they're stronger in general and can hunker down for defense.

The classes and their applications fit familiar archetypes, which should let new players jump into their favored class. The Engineer, represented by Baird, can lay down temporary sentry guns and repair the fences that slow down invading Locusts--but he can only repair, so once a structure is down it's gone for good. The Soldier (Cole) packs more firepower, and can drop ammo boxes. A Scout (Paduk) can grapple to areas inaccessible by the rest of the crew and expose enemy positions with a Beacon grenade. Finally, the Medic (Sofia) can throw her own Stim healing grenade.

Each is useful in its own right, but during an extended play session I was surprised to find how well the powers could work together. An ammo box laid next to an engineer, for example, will keep his repair gun constantly refilled so a structure doesn't go down while he reloads. The Locusts have their own tiers of Beasts with some minor revisions, which serve very similar roles: Tickers to take down defenses, Kantus to heal, and so on. These similarly reward team work, as any one Locust will often be overwhelmed by COG forces.

We only had access to one map, split into three sections as the Locusts pushed further inward. Each section splits into corridors to keep the COGs on their toes defending multiple points. Play ends when the Locust team takes down a COG generator in the third section, or time runs out. Then the teams switch roles, and whichever took down the generator the fastest is declared the winner. I appreciated being pushed into diversifying, since it assures every match will have me in both roles.

Epic claims that the other new mode, Free-for-All, was based directly on the community creating it themselves through some custom rule sets. I expected this experience to be more jarring, and while it was definitely more chaotic than the team-based play, I fell into a comfortable groove once I discovered my weapon of choice. It took some adjustment to playing for myself instead of on a team in the Gears milieu, but after the initial shock it made perfect sense.

The most dynamic change that comes with the advent of FFA is the need to watch your back from all sides, at all times. The new map selection we played facilitated this kind of play, as they often featured tight corridors with several openings on every side. This gave me some temporary safety to catch my breath, but forced me and the players to move frequently and keep the pace going. Hardly ever did I find someone in a safe spot, and if I did, it was never safe for long.

Both of the new modes add elements to the series that it wasn't built to handle. The team-based objectives rely on specialized maps, and the FFA throws out any semblance of cooperative play in exchange for a much faster pace. But as odd as both of them are as diversions from the norm, neither felt tacked on or out of place. They can stand alongside the more traditional modes to grant the game more variety. Longevity has never been a problem for Gears multiplayer, and with radical shifts in modes, it will probably be quite a while before the community squeezes everything it can out of Judgment.

This Gears of War: Judgment multiplayer preview was based on a pre-release Xbox 360 demo of the game.