This has been removed from Heroes of the Storm. 
Tier 2 (Hero Level 4)
Cooldown: 25 seconds
Activate to increase Basic Attack damage by 50% for 5 seconds. Each attack costs 10 Mana.
Patch changes[]
(Patch February 2, 2016) Note: Will now dismount Tyrande on activation.- (Patch October 6, 2015) Note: Basic Attack damage bonus increased from 40% to 50%.
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