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Bash
Gives a 25% chance for melee heroes, and 10% chance for ranged heroes to bash on attack
Stuns for 1.4 seconds
Has a 2 second cooldown
Does not function with other Cranium Bashers, Abyssal Blades, Troll Warlord's Bash, Slithereen Guard's Bash, Faceless Void's Time Lock or Spiritbreaker's Greater Bash

Overwhelm
Disables a target unit for 2 seconds.
Can be cast on magic immune units.
Costs 150 mana, has a 60 seconds cooldown, and a 140 cast range