Berserk is a status effect that causes all damage dealt to the enemy to be doubled until the end of the turn. For example, a Wakizashi used with a 4 will do 8 damage instead of 4. The effect stacks and decreases by 1 at the end of the player's turn, but doesn't increase damage any further than double.

Any self-damage dealt via equipment like Trick or Treat or Double Edge will not be doubled.

• Angel Investor
• Beetle Dash+
• Equilibrium
• Sugar Rush

It is also granted by the Limit Break Berserk used in the episode Thief: Reunion.

The workout Thief Technique in the Warrior: Reunion episode also grants the same Limit Break.