Knowledge Pool + Teferi, Mage of Zhalfir
Asked by Kurozake 5 years ago
Hey, I am slightly confused about the Knowledge Pool + Teferi, Mage of Zhalfir lock. My understanding about it is the following and I would like to know if that's correct:
Player A controls Knowledge Pool + Teferi, Mage of Zhalfir
- Player B casts any spell from their hand during their turn (mainphase) -> B's spell goes onto the empty stack
- A's Knowledge Pool trigger goes onto the stack above B's Spell
- A's Knowledge Pool trigger starts resolving -> B's spell is sent from the stack into exile -> B tries to cast a spell out of Knowledge Pool -> B's spell cast is blocked because A's Knowledge Pool trigger is still on the stack (no empty stack available for sorcery speed) -> Knowledge Pool trigger finishes resolving and leaves the stack
- The stack is now empty again.
I apologize if this has been clearified already in another post and I just didn't find it. Please tell me if my understanding about this is correct or if there's something wrong or missing.
Thank you all in advance!
I don't think the "combo" works at all.
While it is correct that, casting a sorcery requires an empty stack
307.1. A player who has priority may cast a sorcery card from their hand during a main phase of their turn when the stack is empty. Casting a sorcery as a spell uses the stack. (See rule 601, “Casting Spells.”),
the same is true for creature spells -
302.1. A player who has priority may cast a creature card from their hand during a main phase of their turn when the stack is empty. Casting a creature as a spell uses the stack. (See rule 601, “Casting Spells.”)
All that being said the rules for Knowledge Pool specifically state that : Timing restrictions based on the card’s type are ignored. For example, you can cast an exiled creature card this way. Other restrictions, such as Spinal Embrace’s “Cast Spinal Embrace only during combat” are not ignored. (2011-06-01)
This means that your opponent can freely cast spells from the Knowledge Pool regardless of Teferi, Mage of Zhalfir restriction.
November 5, 2018 1:08 p.m.
Madcookie - the lock does work, due to the rule you cited:
Timing restrictions based on the card’s type are ignored. For example, you can cast an exiled creature card this way. Other restrictions, such as Spinal Embrace’s “Cast Spinal Embrace only during combat” are not ignored. (2011-06-01)
Teferi creates an “other restriction” on the card, which is not ignored. The fact that it references sorceries, a card type, specifically does not implicate the “restrictions based on the card’s type” portion of the ruling. That phrase, “whenever you could cast a sorcery” is a term of art used to say “when you have priority and the stack is empty”, and does not specifically care about card type, though a card type is referenced as an example.
November 5, 2018 1:21 p.m. Edited.
I Googled around and most people agree with you. I even saw the combo on the MTGGoldfish's channel and it works on MTGO but I just don't see the logic. Lets recap:
Rules of MTG : sorcery and creature spells can be cast on your turn while the stack is empty. (timing restriction - main phase, empty stack)
Teferi, Mage of Zhalfir: your opponent can cast spells only while the stack is empty (timing restriction - main phase, empty stack)
Bonus Teferi rules: If a spell or ability lets an opponent cast a card as part of its effect (such as suspend and rebound do), that opponent can’t cast that card since the currently resolving ability is still on the stack. This is true even if that card is an instant. (timing restriction for other abilities - beginning of upkeep or cast not in your main phase, empty stack)
Knowledge Pool rules: Ignore timing restrictions when resolving this ability (main phase, empty stack) but not other effects (must be cast during other part of turn Spinal Embrace or limiting effects not regarding timing Curse of Exhaustion)
Apparently Teferi, Mage of Zhalfir is too OP and his rules beat my logic. I was wrong and I guess I'll go away now :(
November 5, 2018 6:57 p.m.
Rhadamanthus says... #5
Madcookie: The one place where your logic goes wrong is in the first step. The MTG rules don't create restrictions on when you're allowed to cast those spells.
The phrase "timing restrictions" is a misnomer, and it frustrates me that some of the rulings notes in Gatherer use it. The reason you're allowed to do pretty much anything in the game is because a rule or card gives you permission to do it. The timing rules are all a system of permissions on when you can do certain things (there's only one true restriction: you can't play lands on other players' turns). If they were restrictions then cards like Knowledge Pool or abilities like Flash wouldn't be able to work at all because one of the key rules of the game is that restrictions are stronger than permissions (i.e. "can't" beats "can").
So the rules give you permission to cast certain spells at certain times. Knowledge Pool gives special additional instruction/permission to cast a spell in the middle of a triggered ability resolving. Teferi, Mage of Zhalfir creates a restriction that says certain players can only cast spells during a main phase on their turn when the stack is empty. Those players can't cast spells from the Pool.
Rhadamanthus says... Accepted answer #1
Yes, that's why it works. "Any time (someone) could cast a sorcery" means during a main phase on that player's turn when the stack is empty. The stack isn't empty when Knowledge Pool's ability is resolving, so that means Teferi, Mage of Zhalfir won't let your opponent cast a spell from the Pool.
November 4, 2018 8:30 p.m.