While a character can be played on its own, players can group with others to
tackle more challenging content. Most end-game challenges are designed in a way
that they can only be overcome while in a group. In this way,
character classes
are used in specific roles within a group. World of Warcraft uses a "rested
bonus" system, increasing the rate that a character can gain experience points
after the player has spent time away from the game. When a character dies, it
becomes a ghost—or wisp for Night Elf characters—at a nearby graveyard.
Characters can be resurrected by other characters that have the ability, or can
self-resurrect by moving from the graveyard to the place where they died.