Braithreachas, Caged

Whenever you cast a spell, put a fury counter on Braithreachas, Caged for each colored mana symbol in that spells mana cost, then if there are 10 or more fury counters on Braithreachas, Caged, destroy all artifacts and create Braithreachas, Liberator, a 20/20 Avatar creature token with haste and trample.