Berserk! is an unlockable active item in The Binding of Isaac, added in the Repentance DLC.

+0.4 speed.
+3 flat damage.
+2 fire rate.
×0.5 fire rate multiplier.

Replaces Isaac's tears with a jaw bone similar to The Forgotten's club. It also uses the same synergies as the club.

This effect lasts for 5 seconds.

The jaw bone deals 3x Isaac's damage when swung, and 1.5x Isaac's damage when thrown.

Swinging the jaw bone will reflect enemy shots, and is able to pick up pickups from a distance.

Killing an enemy while in Berserk mode will increase the duration of the effect by 1 second, and grant very brief invincibility that prevents damage from exploding enemies. Duration cannot be increased by more than 5 seconds.

Each enemy killed will also grant +0.4 speed until the effect ends.

Isaac is unable to die while in Berserk mode. His health can go down to 0, but he will not die until the effect ends. During this time, he can heal himself and cheat death.

The item starts at 50% charge when picked up. It is charged by dealing damage to enemies instead of clearing rooms or picking up batteries. To fully charge it, Isaac must deal damage equal to 120 + 40 × CurrentFloor.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this item for the previous Repentance version, check this page instead.

Defeat Delirium as Tainted Samson.

Berserk! can be found in the following item pools:

The following tags are applied to this item:

The following special synergies and interactions for Berserk! have been documented.

* Note that not all possible synergies and interactions are listed here.

Below is the Internal Item Description as shown in-game.
Note that some stat changes are not displayed here. Please see the main description for the full effects.

Berserk!

• Triggers a berserker mode for 5 seconds, replacing tears with a melee attack and granting increased damage and speed
• Killing an enemy while in berserker mode extends its duration by 1 second
• Berserker mode also prevents death, but Isaac will die if his health is still 0 when the effect ends
• This item charges from taking damage and from damage dealt to enemies. Does not gain charges from room clears
• Abyss: x1 locust .75x Isaac's damage
• Book of Virtues: x1 middle wisp - 10 hp - doesn't shoot

• Check out the item description on the external Isaac Wiki.