503.10. To copy a spell means to put a copy of the spell onto the stack; a copy of a spell isn’t “played.” In addition to copying the characteristics of the spell, all decisions made when the spell was played are copied. These include mode, targets, the value of X, and optional additional costs such as buyback. (See rule 409, “Playing Spells and Activated Abilities.”) Choices that are normally made on resolution are not copied. If an effect of the copy refers to objects used to pay its costs, it uses the objects used to pay the costs of the original spell. A copy of a spell is controlled by the player who put it on the stack. A copy of a spell is itself a spell, but it has no spell card associated with it. It works just like a normal spell: it can be countered or it can resolve, and it uses the same timing rules as normal spells.

Example: A player plays Fork, targeting an Emerald Charm. Fork reads, “Put a copy of target instant or sorcery spell onto the stack, except that it copies Fork’s color and you may choose new targets for the copy.” Emerald Charm reads, “Choose one – Untap target permanent; or destroy target non-Aura enchantment; or target creature loses flying until end of turn.” When the Fork resolves, it puts a copy of the Emerald Charm on the stack. The copy has the same mode that was chosen for the original Emerald Charm. It does not necessarily have the same target, but only because Fork allows choosing of new targets.

Example: Fling is an instant that reads, “As an additional cost to play Fling, sacrifice a creature. / Fling deals damage equal to the sacrificed creature’s power to target creature or player.” When determining how much damage a copy of Fling deals, it checks the power of the creature sacrificed to pay for the original Fling.

503.10a A copy of a spell in a zone other than the stack ceases to exist. A copy of a card in any zone other than the stack or the in-play zone ceases to exist. This is a state-based effect. See rule 420.

503.11. If an effect refers to a permanent by name, the effect still tracks that permanent even if it changes names or becomes a copy of something else.

Example: An Unstable Shapeshifter copies a Crazed Armodon. Crazed Armodon reads, “{G}: Crazed Armodon gets +3/+0 and gains trample until end of turn. Destroy Crazed Armodon at end of turn. Play this ability only once each turn.” If this activated ability of the Shapeshifter is played, the Shapeshifter will be destroyed at end of turn, even if it’s no longer a copy of Crazed Armodon at that time.

503.12. An effect that instructs a player to “play a copy” of an object follows the rules for playing spells and abilities, except that the copy is played while another spell or ability is resolving. Playing a copy of a nonland object follows steps 409.1a-409.1h of rule 409, “Playing Spells and Activated Abilities," then the copy becomes played. The played copy is a spell on the stack, and just like any other spell it can resolve or be countered.

504.1. Two cards (Illusionary Mask and Ixidron) and the morph ability (see rule 502.26) allow spells and permanents to be face down.

504.2. Face-down spells on the stack, face-down permanents in play, and face-down cards in the phased-out zone have no characteristics other than those listed by the ability or rules that allowed the card, spell, or permanent to be turned face down. Any listed characteristics are the copiable values of that object’s characteristics. (See rule 418.5, “Interaction of Continuous Effects,” and rule 503, “Copying Objects.”) Objects that are put into play face down are turned face down before they come into play, so the permanent’s comes-into-play abilities won’t trigger (if triggered) or have any effect (if static). Objects that are played face down are turned face down before they are put onto the stack, so effects that care about the characteristics of a spell will see only the face-down spell’s characteristics.

504.3. At any time, you may look at a face-down spell you control on the stack, a face-down permanent you control, or a face-down card in the phased-out zone you controlled when it phased out. You can’t look at face-down cards in any other zone, face-down spells or permanents controlled by another player, or face-down cards in the phased-out zone last controlled by another player. The ability or rules that allow a permanent to be face down may also allow the permanent’s controller to turn it face up. Spells normally can’t be turned face up.

504.4. If you control multiple face-down spells on the stack or face-down permanents in play, you must ensure at all times that your face-down spells and permanents can be easily differentiated from each other. This includes, but is not limited to, knowing the order spells were played, the order that face-down permanents came into play, which creature attacked last turn, and any other differences between face-down spells or permanents. Common methods for distinguishing between face-down objects include using counters or dice to mark the different objects, or clearly placing those objects in order on the table.

504.5. As a face-down permanent is turned face up, its copiable values revert to its normal copiable values. Any effects that have been applied to the face-down permanent still apply to the face-up permanent. Any abilities relating to the permanent coming into play don’t trigger and don’t have any effect, because the permanent has already come into play.

504.6. If a face-down permanent moves from the in-play zone to any zone other than the phased-out zone, its owner must reveal it to all players as he or she moves it. If a phased-out face-down object moves to any zone other than the in-play zone, its owner must reveal it as he or she moves it. If a face-down spell moves from the stack to any zone other than the in-play zone, its owner must reveal it to all players as he or she moves it. At the end of each game, all face-down objects in play, in the phased-out zone, or on the stack must be revealed to all players.

504.7. If a face-down permanent becomes a copy of another permanent, its copiable values become the copiable values of that permanent, as modified by its face-down status. Its characteristics therefore remain the same: the characteristics listed by the ability or rules that allowed it to be turned face down. However, if it is turned face up, its copiable values become the values it copied from the other permanent.

504.8. If a face-down permanent would have an “As [this permanent] is turned face up . . .” ability after it’s turned face up, that ability is applied while that permanent is being turned face up, not afterward.

505.1. Split cards have two card faces on a single card. The back of a split card is the normal Magic: The Gathering card back.

505.2. In every zone except the stack, split cards have two sets of characteristics and two converted mana costs. As long as a split card is a spell on the stack, only the characteristics of the half being played exist. The other half’s characteristics are treated as though they didn’t exist.