This has been removed from Heroes of the Storm. 
Tier 4 (Hero Level 10)
Mana: 75
Cooldown: 40 seconds
Greymane shapeshifts into a Human and fires a bullet that hits the first enemy Hero in its path, dealing 197.6 (+4% per level) damage. For 5 seconds, their Armor is lowered by 25, taking 25% more damage. Each time Greymane damages the Marked Hero, the duration is refreshed.
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(Patch January 27, 2017) Note: Marked for the Kill now correctly reduces the target’s armor by 25, increasing their damage taken.- (Patch January 24, 2017) Note: Fixed an issue in which this could still be applied to Invulnerable Heroes.
- (Patch August 24, 2016) Note: Damage increased from 68 to 190.
- (Patch July 27, 2016) Note: Cooldown reduced from 50 to 40 seconds.
- (Patch July 12, 2016) Note: New Functionality: When Greymane deals damage to the Marked target, the duration of the Vulnerable effect is refreshed. This can happen indefinitely. No longer allows you to reactivate to leap to the opponen; Reduced cooldown from 60 to 50 seconds; Range reduced by 40%.
- (Patch March 29, 2016) Note: Bullet range increased by 25%; Bullet speed increased by 45%.
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