Frenzy

Version 0.30: This article may not be up to date for the latest stable release of Crawl.

Frenzy is a status effect. During frenzy, monsters turn "neutral", causing them to attack anything in sight - friend or foe. This also applies the haste and might status effect. Afterwards, they are slowed for a brief time. Like berserk, frenzied monsters can't cast spells.

When a source of frenzy is used against the player, the berserk effect is applied instead.

Sources of Frenzy

Frenzy can be afflicted by:

Discord: A level 8 Hexes spell which attempts to frenzy all monsters in sight.
Datura-tipped dart: Throwing weapon which can apply the frenzy effect to vulnerable monster upon hit.
Orbs of mayhem: May frenzy a monster whenever you kill.

History

Prior to 0.28, non-natural creatures would not get the haste or might effect. You would not get XP when a frenzied monster died. Gods which hated attacking neutral monsters would forbid attacking a frenzied one. Also, in 0.28, frenzy was made dispellable again.
In 0.27, frenzy was made non-dispellable.
Prior to 0.13, frenzy could only affect natural creatures.