Multiple Knowledge pool questions

Asked by Ziggy101 7 years ago

In a four player game: Mr. A control a Knowledge Pool that imprinted Kozilek, Butcher of Truth and Mr. B controls a Knowledge Pool that imprinted Jace Beleren

2 other opponents Mr. C and D, don't control a Knowledge Pool

Question 1.Mr. C casts Brainstorm on his own turn. Which Knowledge Pool exiles Brainstorm ?

Question 2.Mr. C casts Brainstorm on Mr. A's turn. Which Knowledge Pool exiles Brainstorm ? Is it Mr. B's?

(Since Mr. A's own Knowledge Pool goes on the stack before Mr. B's Knowledge Pool and Mr B's resolves first, leaving no spells to exile for Mr. A's)

Question 3.Similar to question 2 but Mr. A casts Ponder on his own turn. Knowledge Pool under control of Mr. B exiles it. Which leaves Mr. A with a Jace Beleren , right?

Countering:

Question 4

Mr. C casts Brainstorm on his turn and Mr. A. casts Pact of Negation in response. Mr. A don't want to counter Mr' C's spell, just pick a spell in Knowledge Pool and need to target something with that counter to cast it at instant speed.

Can Mr. A cast Pact of Negation that targets Mr. C's Brainstorm or do Mr. A have to wait until after Brainstorm is exiled, and Knowledge Pool have cast out another spell. So Mr. A casts Pact of Negation targeting the new spell? So he himself can choose from a Knowledge Pool

Hope all of this make sense.

Thanks

BlueScope says... Accepted answer #1

Mostly everything of the above can be answered with the APNAP principle - when there's multiple abilities trying to enter the stack at the same time, they are put there in active player, non-active player(s) order. Since the stack resolves last-in, first-out, whoever's Knowledge Pool triggers last will exile the spell that's been cast.

Therefore, assuming the turn order is A-B-C-D, this is what happens for each question (using "A" as a placeholder for "player A's Knowledge Pool"):

  1. B exiles the spell
  2. B exiles the spell
  3. Only if A chooses to cast Jace Beleren - they may choose not to cast anything, but they may not choose to cast their Ponder that's just been exiled

Now, for question 4, both Pools trigger, and once their abilities are put on the stack, A gets to respond to the second trigger, casting Pact of Negation, which will in turn trigger both Pools. For both players, only B's Knowledge pool is relevant, so when that ability resolves and exiles Pact of Negation, it will let them cast Jace Beleren instead. Jace will become the topmost object of the stack, will resolve as normal unless anything else happens, and A resolves the Jace. Now, after A's Knowledge Pool trigger resolves (it resolves, but does nothing, as the spell it triggered for left the stack already), the topmost object of the stack is B's Knowledge Pool trigger that will exile Brainstorm and would allow them to cast the only card imprinted in B's Pool at tis point - Pact of Negation. However, since there are no spells on the stack, C won't be able to cast that card.

December 6, 2016 10:54 a.m.

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