In Diablo II, the quests are a series of missions of which most are integral to proceeding in the single-player game. For example, without the Cube, the Khalim's Heart, Eye and Brain, and Khalim's Flail, the single-player character cannot get beyond Act III. However, in multiplayer, an advanced character can open a Town Portal from a waypoint beyond the blocked part, enabling a less-experienced player to bypass the quest entirely. Players are advised to complete all quests, so that the game's story can be developed to the fullest.