The shard Power of Storms gives the hero a 15% chance to rapidly restore mana for 4 seconds. Now all new heroes don't use Mana and the shard does not provide any benefit for their resource gain. I tested it on mystic and she gained not more appeasement when hitting or collecting. The shard says for all heroes  which is missleading.

Steps to reproduce:

• start the game
• equip a none mana hero with the power of storms shard (e.g. Mystic)
• start a map
• fight in the map
• notice you don't get increased appeasement gain ever

Expected result:

You either get increased special ressources gain with none mana heroes or it does not say Valid For: All.