Griselbrand has the same wording as the Moxes (“The first black card in your hand gains full mana”)
But the Moxes work differently: They add mana to the first card in your hand that can gain mana, so if the first X card in your hand is already full of mana, it will fill the next one.
But with Griselbrand, if the first black card in your hand is already full of mana, the next black card in your hand will gain no mana.
Thank you for all the information provided, this issue will be investigated!
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