In Mortal Kombat vs. DC Universe, the brutal combatants of the Mortal Kombat invade Metropolis and the rest of the DC Universe after Superman defeats the supervillain Darkseid. The Man of Steel accidentally overloads one of Darkseid's teleportation devices, causing a rift to open into Mortal Kombat's Earthrealm. Worse yet, the infernal rage of that reality's demonic Outworld fuses Darkseid with Mortal Kombat's villain Shao Kahn to become a new threat: Dark Kahn.

The game's Story Mode recounts this crossover invasion from both the DC and Mortal Kombat perspectives, as the DC heroes suspect another Darkseid plot and their Earthrealm counterparts fear another Outworld assault. Infecting both sides is the mysterious "rage" energy that overwhelms their senses, causing them to see friends as enemies and supercharging their fighting abilities.

In addition to the Story mode, the game also offers a more traditional Arcade Mode featuring the standard Mortal Kombat 10-fight contest from years past. Players can chose to play Mortal Kombat only, DC only and mixed fights, but in either case the ultimate villain is Dark Kahn.

The game features 20 combatants, 10 from each universe, with two unlockable characters. The Mortal Kombat side features Scorpion, Subzero, Sonya, Shang Tsung, Kitana, Jax, Liu Kang, Raiden, Kano and Baraka, while DC is represented by the Joker, Catwoman, the Flash, Superman, Batman, Wonder Woman, Deathstroke, Lex Luther, Captain Marvel and Green Lantern. The unlockables are Darkseid for the DC side and Shao Kahn for Mortal Kombat.

Venues for battles include Apokolips, the Bat Cave, the Fortress of Solitude, Gotham City, Netherrealm, Metropolis, the U.N. Space Station and Wu Shi Academy. Each arena features multiple levels; knocking an opponent off one of these tiers initiates a "Free Fall Kombat" mini-game in which the combatants beat each other senseless in hopes of executing a special move before they smash into the ground. Some levels also include walls that opponents can be thrown through, triggering a "test your might" button-mashing mini-game.

Whether in story or arcade mode, gameplay represents a streamlined, less violent version of that featured in previous Mortal Kombat titles. Players hit a combination of game controller buttons to execute basic and advanced fighting combinations as well as super-powered moves. Each character has two finishing moves (called "Fatalities" for villains and "Heroic Brutalities" for DC heroes), allowing them to kill or (in the case of Heroic Brutalities) incapacitate their enemies in spectacular fashion. A character's regular and super moves are documented via a quick-reference move list in the game, but fatalities need to be discovered.

Mortal Kombat vs. DC Universe supports ranked, casual and private matches, as well as support for multiplayer game rooms.

A kinder, gentler Kombat

Mortal Kombat vs. DC Universe is an unlikely matchup. Granted, DC heroes have had just about every crossover imaginable, including ones pitting its heroes against Aliens, Predator and even H.P Lovecraft's Cthulhu mythos, but there weren't many fans clamoring for this particular inter-planar invasion.

And yet here it is, and the biggest surprise is that it more or less works. That's largely because it features something that a lot of fighting games (Mortal Kombat included) don't have: a coherent story. Penned by writers Justin Gray and Jimmy Palmiotti (both of whom worked on DC's recent Countdown title), the story mode features a plot that could have been ripped from any of DC's titles. The branching MK and DC storylines work well, creating plausible reasons for the heroes from each universe to battle each other. This leads to some amusing misunderstandings as the Kombatants trade stories of rage-infused attacks by red-suited attackers with lightning bolts on their chests ... and don't realize that Flash and Captain Marvel are two very different characters.

The characters are also true to their motivations; when Joker realizes his combat skills have been supercharged, he not only goes and takes out two Mortal Kombatants but then goes on his own private vendetta to hunt down (and temporarily defeat) Batman.

That said, most people don't play Mortal Kombat for the story, they play for the violence and gore. The game has plenty of the former, but the gore's been toned down considerably to win a T rating. Blood still flows freely from punches, kicks and other moves, but the lethal pit traps from earlier games are gone, and Scorpion won't be ripping anyone's spine out. The myriad forms of "fatality" (including Friendships, Animalities and Hari Kari) have been removed, as have the complicated "Kreate-a-Fatality" of Mortal Kombat: Armageddon.

The game can still be exceedingly violent. DC fans who can't stand the thought of seeing Superman killed by playing cards to the head thrown by the Joker, or Deathstroke snapping the neck of Green Lantern, will likely want to avoid the game. While the true heroes in the game never kill—Batman, Superman, Wonder Woman and the others have "Heroic Brutalities" rather than traditional fatalities—it's still disconcerting to see anyone kill Superman whose name isn't "Doomsday."

The sheer diversity of the game has been greatly reduced from previous Mortal Kombat titles; while Armageddon had 60 Kombatants, there are only 22 in this game, half of whom are from the Mortal Kombat universe. While almost all of the original Mortal Kombatants can be found in the game—with the notable exception of Johnny Cage—the number of options will likely disappoint die-hard MK fans. The game somewhat makes up for this by re-creating its Kombatants' signature moves (it just wouldn't be Mortal Kombat without Scorpion's lethal grappling hook), but it feels diminished compared to earlier games.

The in-game engine renders the characters well, and there are plenty of small but nice touches, such as costumes ripping as combat proceeds, the rippling of Superman's cape and subtle background effects like cherry blossoms falling at the Wu Shi Academy. There are occasionally jarring effects, such as the way cybernetic soldier Jax's dog tags seem to defy physics, the unnatural movement of Captain Marvel's cap and the way all of the women in the game have oversized breasts that seem utterly incompatible with fighting. These occasional flaws aside, the game generally looks great, and the transitions from cinematics to fighting are surprisingly seamless.

Mortal Kombat vs. DC Universe works best as a casual fighting game. Those going into it looking for the complexity of previous games may be frustrated by it, but the more gradual learning curve should be appealing to those who gave up the franchise out of frustration with seemingly endless killer combos and encyclopedia-length move lists.