"Borderlands 2" review: A unique sequel in every sense The action rarely slows down in Borderlands 2. Credit: 2K Games (CBS News) Few titles have tapped into gamers' obsession with exploration and discovery as successfully as 2K Games' 2009 sleeper hit "Borderlands." The vast, over-the-top world coupled with a seemingly endless amount of loot (a mind-boggling array of weapons and ammo) and the ability to play with three other players created a compulsive concoction that struck a nerve with gamers. "Borderlands 2" improves every facet of the original, delivering a game that will please role-playing game, open-world and first-person shooting fans, long after the closing credits. You choose from four classes - Gunzerker, Siren, Commando and Assassin - and each class has a special ability. The Gunzerker can duel wield any two weapons at once; the Siren can suspend enemies in midair; the Commando creates turrets; and the Assassin can create a decoy of himself and turn invisible. Each ability can be activated once a meter is filled and then there's a cool-down period before it can be used again. Each class has three skill trees, giving you the ability to upgrade your character in myriad ways. Anything from boosting your weapons' power to reducing the cool-down time for your special ability can be manipulated. Experience points are at the heart of this system. Killing enemies, completing side and main missions, and discovering new locations nets XP. Once you accumulate enough XP, you level up, giving you the chance to choose another upgrade. Gearbox also added Badass Points, which are awarded for specific in-game activities. Once you've accumulated enough of these points, you can trade them for upgrades, which carry over if you decide to play as another class. But the real pull in the Borderlands universe is discovering the vast weaponry. Just like the original, "Borderlands 2" boasts a countless assortment of guns - anything from rocket launchers to submachine guns. The amount of creativity that has gone into creating each weapon is astounding. One specific shotgun shoots one round then can be thrown at enemies and explodes on impact. Some guns discharge unique ammunition, such as exploding and incendiary rounds. Some ammo is more effective against certain enemy types, providing a level of depth to the gameplay. Gearbox also put a lot of care into creating a wide variety of enemies. Mechs, mutants and maniacal mercenaries are just some of the foes littering the world. Enemies are more prone to dodge and use cover more wisely than in the original title. It is possible to destroy the mechs' limbs to slow their charge, but even if you destroy their legs they will use their arms to advance while throwing grenades. The sheer level of activities is overwhelming. Distractions are everywhere, creating a sense of exploration that only exceptional open-world games can attain. A number of times I found myself veering off course from the original mission because of a newly discovered town that garnered my attention. Gearbox and 2K Games have delivered a unique experience that is a true sequel in every sense. The world is teeming with adventure and will compel you to explore its varied landscapes and mission structures. The overabundance of loot makes opening every chest or killing every foe a moment of anticipation few games can match. And when you factor in bringing three friends along for the ride, Borderlands 2 is one of this year's can't-miss titles. Borderlands 2 is rated M for Mature by the ESRB. It is available for the PC, PlayStation 3 and Xbox 360.