Definitely not my favorite Ancient bonus. The big hurdle for it is that so many enemies have friends or Artifact charges, and in those fights it doesn't manage to shut them down. Also, what's the point of applying lots of weak to the enemy you're dealing all your damage to in a fight with multiple enemies; you're going to kill that enemy first presumably, and then the Weak will be wasted. That said, it still creates an absurd amount of output for 0 energy.
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