If a spell or activated ability has a mana cost, alternative cost, additional cost, and/or activation cost with an {X}, [-X], or X in it, and the value of X isn't defined by the text of that spell or ability, the controller of that spell or ability chooses and announces the value of X as part of casting the spell or activating the ability. (See rule 601, "Casting Spells.") While a spell is on the stack, any X in its mana cost equals the announced value. While an activated ability is on the stack, any X in its activation cost equals the announced value.

If a spell or activated ability has a mana cost, alternative cost, additional cost, and/or activation cost with an {X}, [-X], or X in it, and the value of X isn't defined by the text of that spell or ability, the controller of that spell or ability chooses and announces the value of X as part of casting the spell or activating the ability. (See rule 601, "Casting Spells.") While a spell is on the stack, any X in its mana cost or in any alternative cost or additional cost it has equals the announced value. While an activated ability is on the stack, any X in its activation cost equals the announced value.

Planeswalkers have their own unique set of subtypes; these subtypes are called planeswalker types. The planeswalker types are Ajani, Ashiok, Bolas, Chandra, Dack, Domri, Elspeth, Garruk, Gideon, Jace, Karn, Kiora, Koth, Liliana, Nissa, Ral, Sarkhan, Sorin, Tamiyo, Tezzeret, Tibalt, Venser, Vraska, and Xenagos. If a player controls two or more planeswalkers that share a planeswalker type, that player chooses one of them, and the rest are put into their owners' graveyards. This "planeswalker uniqueness rule" is a state-based action. See rule 704.

Planeswalkers have their own unique set of subtypes; these subtypes are called planeswalker types. The planeswalker types are Ajani, Ashiok, Bolas, Chandra, Dack, Daretti, Domri, Elspeth, Freyalise, Garruk, Gideon, Jace, Karn, Kiora, Koth, Liliana, Nahiri, Narset, Nissa, Nixilis, Ral, Sarkhan, Sorin, Tamiyo, Teferi, Tezzeret, Tibalt, Ugin, Venser, Vraska, and Xenagos. If a player controls two or more planeswalkers that share a planeswalker type, that player chooses one of them, and the rest are put into their owners' graveyards. This "planeswalker uniqueness rule" is a state-based action. See rule 704.

An ability word appears in italics at the beginning of some abilities. Ability words are similar to keywords in that they tie together cards that have similar functionality, but they have no special rules meaning and no individual entries in the Comprehensive Rules. The ability words are battalion, bloodrush, channel, chroma, constellation, domain, fateful hour, ferocious, grandeur, hellbent, heroic, imprint, inspired, join forces, kinship, landfall, lieutenant, metalcraft, morbid, parley, radiance, raid, strive, sweep, tempting offer, threshold, and will of the council.

An ability word appears in italics at the beginning of some abilities. Ability words are similar to keywords in that they tie together cards that have similar functionality, but they have no special rules meaning and no individual entries in the Comprehensive Rules. The ability words are battalion, bloodrush, channel, chroma, constellation, domain, fateful hour, ferocious, formidable, grandeur, hellbent, heroic, imprint, inspired, join forces, kinship, landfall, lieutenant, metalcraft, morbid, parley, radiance, raid, strive, sweep, tempting offer, threshold, and will of the council.

Layer 7e: Effects that switch a creature's power and toughness are applied. Such effects take the value of power and apply it to the creature's toughness, and take the value of toughness and apply it to the creature's power.

Example: A 1/3 creature is given +0/+1 by an effect. Then another effect switches the creature's power and toughness. Its new power and toughness is 4/1. A new effect gives the creature +5/+0. Its "unswitched" power and toughness would be 6/4, so its actual power and toughness is 4/6.

Example: A 1/3 creature is given +0/+1 by an effect. Then another effect switches the creature's power and toughness. Its new power and toughness is 4/1. If the +0/+1 effect ends before the switch effect ends, the creature becomes 3/1.

Layer 7e: Effects that switch a creature's power and toughness are applied. Such effects take the value of power and apply it to the creature's toughness, and take the value of toughness and apply it to the creature's power.

Example: A 1/3 creature is given +0/+1 by an effect. Then another effect switches the creature's power and toughness. Its new power and toughness is 4/1. A new effect gives the creature +5/+0. Its "unswitched" power and toughness would be 6/4, so its actual power and toughness is 4/6.

Example: A 1/3 creature is given +0/+1 by an effect. Then another effect switches the creature's power and toughness. Its new power and toughness is 4/1. If the +0/+1 effect ends before the switch effect ends, the creature becomes 3/1.

Example: A 1/3 creature is given +0/+1 by an effect. Then another effect switches the creature's power and toughness. Then another effect switches its power and toughness again. The two switches essentially cancel each other, and the creature becomes 1/4.

If a card with morph is manifested, its controller may turn that card face up using either the procedure described in rule 702.36d to turn a face-down permanent with morph face up or the procedure described above to turn a manifested permanent face up.

If a card with morph is manifested, its controller may turn that card face up using either the procedure described in rule 702.36e to turn a face-down permanent with morph face up or the procedure described above to turn a manifested permanent face up.

To cast a card using its morph ability, turn it face down. It becomes a 2/2 face-down creature card with no text, no name, no subtypes, and no mana cost. Any effects or prohibitions that would apply to casting a card with these characteristics (and not the face-up card's characteristics) are applied to casting this card. These values are the copiable values of that object's characteristics. (See rule 613, "Interaction of Continuous Effects," and rule 706, "Copying Objects.") Put it onto the stack (as a face-down spell with the same characteristics), and pay {3} rather than pay its mana cost. This follows the rules for paying alternative costs. You can use morph to cast a card from any zone from which you could normally play it. When the spell resolves, it enters the battlefield with the same characteristics the spell had. The morph effect applies to the face-down object wherever it is, and it ends when the permanent is turned face up.

To cast a card using its morph ability, turn it face down. It becomes a 2/2 face-down creature card with no text, no name, no subtypes, and no mana cost. Any effects or prohibitions that would apply to casting a card with these characteristics (and not the face-up card's characteristics) are applied to casting this card. These values are the copiable values of that object's characteristics. (See rule 613, "Interaction of Continuous Effects," and rule 706, "Copying Objects.") Put it onto the stack (as a face-down spell with the same characteristics), and pay {3} rather than pay its mana cost. This follows the rules for paying alternative costs. You can use a morph ability to cast a card from any zone from which you could normally play it. When the spell resolves, it enters the battlefield with the same characteristics the spell had. The morph effect applies to the face-down object wherever it is, and it ends when the permanent is turned face up.

You can't cast a card face down if it doesn't have morph.

You can't cast a card face down if it doesn't have a morph ability.

Any time you have priority, you may turn a face-down permanent you control face up. This is a special action; it doesn't use the stack (see rule 115). To do this, show all players what the permanent's morph cost would be if it were face up, pay that cost, then turn the permanent face up. (If the permanent wouldn't have a morph cost if it were face up, it can't be turned face up this way.) The morph effect on it ends, and it regains its normal characteristics. Any abilities relating to the permanent entering the battlefield don't trigger when it's turned face up and don't have any effect, because the permanent has already entered the battlefield.

Any time you have priority, you may turn a face-down permanent you control with a morph ability face up. This is a special action; it doesn't use the stack (see rule 115). To do this, show all players what the permanent's morph cost would be if it were face up, pay that cost, then turn the permanent face up. (If the permanent wouldn't have a morph cost if it were face up, it can't be turned face up this way.) The morph effect on it ends, and it regains its normal characteristics. Any abilities relating to the permanent entering the battlefield don't trigger when it's turned face up and don't have any effect, because the permanent has already entered the battlefield.

See rule 707, "Face-Down Spells and Permanents," for more information on how to cast cards with morph.

See rule 707, "Face-Down Spells and Permanents," for more information on how to cast cards with a morph ability.

Some cards and abilities allow spells and permanents to be face down.

Some cards allow spells and permanents to be face down.

Anything that asks for a particular characteristic of a split card while it's in a zone other than the stack gets two answers (one for each of the split card's two halves). Anything that asks for a particular characteristic of a fused split spell gets two answers. Anything that asks for a particular characteristic of a split card while it's a spell on the stack or that asks for the converted mana cost of a fused split spell gets one answer.

Example: Infernal Genesis has an ability that reads, "At the beginning of each player's upkeep, that player puts the top card from his or her library into his or her graveyard. He or she then puts X 1/1 black Minion creature tokens onto the battlefield, where X is that card's converted mana cost." If the top card of your library is Assault/Battery, which has converted mana costs of 1 and 4, when this ability resolves, you simultaneously put one and four creature tokens onto the battlefield, for a total of five.

Example: Spell Blast says "Counter target spell with converted mana cost X." If a player wants to cast Spell Blast and choose the fused split spell Breaking/Entering, which has mana costs {U}{B} and {4}{B}{R}, as the target, that player must choose 8 as the value of X.

Anything that asks for a particular characteristic of a split card while it's in a zone other than the stack gets two answers (one for each of the split card's two halves). Anything that asks for a particular characteristic of a fused split spell gets two answers. Anything that asks for a particular characteristic of a split card while it's a spell on the stack or that asks for the converted mana cost of a fused split spell gets one answer.

Example: Spell Blast says "Counter target spell with converted mana cost X." If a player wants to cast Spell Blast and choose the fused split spell Breaking/Entering, which has mana costs {U}{B} and {4}{B}{R}, as the target, that player must choose 8 as the value of X.

The current phase and/or step ends. The game skips straight to the cleanup step. Skip any phases or steps between this phase or step and the cleanup step.

The current phase and/or step ends. The game skips straight to the cleanup step; skip any phases or steps between this phase or step and the cleanup step. If an effect ends the turn during the cleanup step, a new cleanup step begins.