The third Diablo returns you to the world of Sanctuary, once again invaded by the demons. Twenty years after the ending of Diablo II, a star has fallen on the city of New Tristram, spawning hordes of undead monsters that the player must defeat. As usual in Diablo series, the game has a trademark dark fantasy atmosphere and is mostly set in gloomy dungeons. The basic gameplay features are the same as in previous Diablo games, but there are many subtle changes. The player can choose one of six character classes (a seventh is available with an expansion). Each class has its unique abilities and class-specific quests. Unlike its predecessors, which used isometric 2D graphics, Diablo III uses 3D, however, it preserves the familiar top-down view. The dungeons are randomly generated and have destructible environments, thanks to the new graphics engine. There’s a new mechanic Skill Runes that is used to improve the character’s skills. Online multiplayer is available through Battle.net. There are both a co-op mode and a PvP mode called Brawling. The players can create hardcore characters who face permadeath if killed. Even in the single-player mode, Diablo II requires a stable internet connection, because of DRM restrictions.