Rules Tip of the Day: A spell or ability may instruct two players to exchange something (for example, life totals or control of two permanents) as part of its resolution. When such a spell or ability resolves, if it can't exchange the chosen things, it has no effect on them.

Q: I play Blistering Firecat face down and equip it with Skullclamp for a 3/1 creature. The next turn I attack and my opponent does not block. If I turn the Firecat face up, do I get it to deliver 8 damage or it goes to the graveyard beforehand due to the Clamp?

A: It goes to the graveyard as soon as you turn it face up because it's an 8/0 creature. Even though Morph doesn't use the stack, you still check State-Based Effects before a player would get priority. The game sees the 0-toughness and puts the Cat in the 'yard before you can move to the Combat Damage Step.

Q: If I use a non-mana source (such as Coretapper, Energy Chamber or Power Conduit) to put a charge counter on Pentad Prism, will the charge counters always be colorless or is there a way to make it colored?

A: The charge counters themselves have no color, nor any color associated with them. You can remove a charge counter to produce any color of mana, not just the color of mana that went into getting the counter on the Prism in the first place.

Q: What happens if I have Volrath's Shapeshifter in play and the top creature card in my graveyard is half of Big Furry Monster? Does it matter which half of the BFM is in the graveyard?

A: Because you only have half the BFM on top of your graveyard, you only get half the text. The good news is you get to choose having either a 99 power or 99 toughness. You can't have both. The other good news is that the value other than the one you chose isn't 0, it's"undefined." A creature with"undefined" power deals infinite damage; a creature with"undefined" power can never have damage equal to its toughness, so it'll never suffer lethal damage. As always, you should be very careful regarding answers to Unglued cards.*

Q: If someone plays Vulshok Battlemaster, and there is Lightning Greaves and some other piece of equipment in play, does the Battlemaster override this or not, because as soon as the Greaves become attached, nothing else can go on there right?

A: When Vulshok Battlemaster comes into play, all the equipment, to include Lightning Greaves, becomes attached to it at once. This ability doesn't target, and the Greaves won't prevent the other equipment from attaching. Once the Greaves is equipped, the creature can no longer be targeted by the equip ability. The Lightning Greaves won't make the other equipment fall off because once it's attached, the equipment doesn't target the creature.

Q: I wanted to play a white weenie deck the other day and use Warrior en-Kor to redirect damage to creatures with protection from (name a color). One of the judges told me that the redirected damage from the En-Kor was white and that my creatures needed protection from white to survive. Is this true? What color is the redirected En-Kor damage?

A: The judge was not correct. You would still refer to the characteristics of the original source of the damage, not to the en-Kor. The en-Kor isn't dealing damage, it's just redirecting it.

Q: Player A activates Mishra's Factory. Player B plays Swords to Plowshares targeting the Assembly Worker. Player A responds by playing Teferi's Response targeting the Swords to Plowshares. Player B responds by playing Cho-Manno's Blessing targeting the Assembly Worker to give it protection from White. Now my questions are: Will Teferi's Response be able to successfully resolve if the Swords to Plowshares target is illegal? Does it mean that it is no longer considered to be targeting its original target (Mishra's Factory)?

A: Here's what happens: Cho-Manno's Blessing resolves, giving Assembly Worker Pro White. Note that you choose the color on resolution, not on announcement. Then Teferi's Response resolves, removing Swords to Plowshares from the stack and Player A draws two cards. The only conditions on Teferi's Response are that its target is a spell or ability that your opponent controls which targets a land you control (which is still true at this point). It has no idea and doesn't really care that the Assembly worker will later become an invalid target for StP. Swords to Plowshares never resolves because it's been removed from the stack.

Q: I play Duplicant, imprinting my opponent's Exalted Angel. The next turn, my opponent uses Astral Slide to remove the Duplicant from the game. When the Duplicant comes back at the end of the turn, will it still be a 4/5 Angel Shapeshifter or will it be a 2/4 Shapeshifter? I would think it would remain a 4/5, since the rules for imprint say that the card remains imprinted on Duplicant as long as it is removed from the game, but I'm not sure if there is an exception if the Duplicant is removed from the game.

A: When the Duplicant comes back into play. it's treated as a new version of the card. You may Imprint something new onto it; if you don't, it'll be 2/4. When it left play, it lost track of whatever it had previously Imprinted. It has no idea that it used to have Exalted Angel Imprinted.

Q: I am at negative life but still alive due to Platinum Angel. I also have in play Volrath's Shapeshifter that is pretending to be some random guy. Because my opponent is a poser and wants to win he decides to Oxidize my Angel. I believe that I stay alive because when the game checks for state based effects after Oxidize breaks my angel, it sees that my Shapeshifter has already turned into an angel during Oxidize's resolution. Is this correct?

A: That's correct. During resolution of Oxidize, Platinum Angel is put in the graveyard. Volrath's Shapeshifter immediately becomes Platinum Angel. After Oxidize is finished resolving, the game checks State-Based Effects and sees that you have 0 or less life, but the Shapeshifter-Angel keeps you from losing.

* Never trust a NetRep when answering an Unglued question. No good can come from it. Here's the REAL answer to the BFM question:

A: Each half of BFM is considered to be the whole card when it's in a zone other than play, so it has the entire text. Your Shapeshifter would be 99/99.

There is no such thing as"undefined" power and toughness in Magic.