http://us.battle.net/heroes/en/forum/topic/20744174735?page=9#171

Hey! I wanted to stop in this thread and let you guys know that the mana cost changes Tyrael received recently aren't the end of the road for him in terms of tweaks we have planned. It won't be a full rework, but we are looking to make a number of changes to some of Tyrael's talents with our next major patch

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