Sierra On-Line announced on Thursday that it is publishing Hellfire, an official add-on disk for Blizzard Entertainment's award-winning Diablo. The add-on disk, scheduled for release in November, is being developed by Synergistic Software (a division of Sierra) and will feature a selection of new weapons, monsters and spells for Blizzard's action-RPG. Hellfire will also include a new character class.

　　Hellfire will follow a new storyline, pitting players against a former minion of Diablo named Na-krul, who is trying to assemble a collection of evil artifacts that have been hidden by his former master. Hellfire will sport 30 new weapons and 20 new monsters, including a skeletal sorcerer, a Lich, a tentacled eyeball named the Psychorb, and a creature dubbed the Hork Demon who spawns smaller replicas of himself named Hork Spawns. Players will also have access to five new spells, including Immolation, Lightning Wall, and Warp, which transports players to the nearest dungeon exit.

　　Little information was released about the new character class, The Monk, except that he would have "a mix of abilities not found in the other classes."

　　Characters created in the single-player version of the original Diablo will be compatible with the add-on, but dungeon delvers hoping to try The Monk out on Battle.net will be disappointed - Hellfire will be single-player only.