One I saw happen quite a bit involved Nivmagus Elemental. The two main things players seemed to misunderstand were both tied to the Elemental’s ability.
The first one is easy: When it says to exile a spell you control, it means a spell on the stack. That Blustersquall in your hand and that Electrickery in your graveyard aren’t spells; they’re cards! Spells only exist on the stack, and permanents only exist on the battlefield. Everywhere else, they are just cards. So you can’t pull spent instants and sorceries out of your bin to power up Nivmagus, nor can you pitch cards from your hand for free. What you have to do is actually pay the mana, pick targets if needed, and cast the spell from wherever, and then exile it with Elemental.
The other thing is, as the reminder text reminds you, your spell won’t resolve. If you feed it to Nivmagus Elemental, it leaves the stack before it resolves. None of its effects happen. Your Blustersquall won’t tap anything, your Electrickery won’t damage anything, your Cyclonic Rift won’t bounce anything, etc.
The last thing worth pointing out is exactly WHEN you have to announce that you’re activating the ability to exile your spell. There’s a default tournament shortcut that says: “A player is assumed to be passing priority after casting a spell or activating an ability unless they say otherwise.” This exists to make Magic a playable game. If you had to explicitly pass priority every time you cast a spell so your opponent could respond (which is technically true according to the Comprehensive Rules), it would just bog down the game with technicalities. So if you cast a spell you intend to exile with the Nivmagus, you can’t wait for your opponent to respond before you activate the ability. Once your opponent passes priority without doing anything, the spell is going to resolve before you have a chance to do so. What you need to do is say, “Cast this spell and exile it with Nivmagus,” or something similar to indicate you’re retaining priority. Otherwise, your only chance to exile your spell is if your opponent chooses to respond to it (e.g., by trying to counter it), in which case you’ll get priority again while both spells are on the stack and can then get some value out of your spell that was going to be countered anyway (in fact, that’s probably the way the Nivmagus was designed to really do its work!).
Today’s Rules Tip written by
Trevor Nuñez