Spells that deal 0 damage will not remove a shield token, nor will they remove a nemesis token from Magus of Cloaks.
Example: Kadir casts Dark Fire from her I breach (Cast: Discard up to two cards in hand. Deal 3 damage for each card discarded this way.) and chooses not to discard any cards from hand. Since Dark Fire deals no damage, it cannot be used to remove a shield token from a minion or a nemesis token from Magus of Cloaks.
