Magic: The Gathering Comprehensive Rules

(such as “All creatures lose flying”).

Example: One effect reads, “White creatures get +1/+1,” and another, “Enchanted creature is white.” The enchanted creature gets +1/+1 from the first effect, regardless of its previous color.

418.5i Some effects switch a creature’s power and toughness. When they’re applied, they take the value of power and apply it to the object’s toughness, and take the object’s toughness and apply it to the object’s power. These effects are applied after all other effects that affect power and toughness. (See rule 418.5a.)

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 a 3/1.

418.6. Text-Changing Effects

418.6a An effect that changes the text of an object changes only those words that are used in the correct way (for example, a Magic color word being used as a color word, a land type word used as a land type, or a creature type word used as a creature type). The effect can’t change a proper noun, such as a card name, even if that proper noun contains a word or a series of letters that is the same as a Magic color word, basic land type, or creature type.

418.6b Effects that add or remove abilities don’t change the text of the objects they affect, so any abilities that are granted to an object can’t be changed by effects that change the text of that object.

418.6c Spells and abilities that create creature tokens use creature types to define both the creature types and the names of the tokens. These words can be changed, because they are being used as creature types, even though they’re also being used as names.

418.6d A creature token’s creature type and rules text are defined by the spell or ability that created the token. These characteristics can be changed by text-changing effects.

419. Replacement and Prevention Effects

419.1. Replacement and prevention effects are continuous effects that watch for a particular event to happen and then completely or partially replace that event. These effects act like “shields” around whatever they’re affecting.

419.1a Effects that use the word “instead” are replacement effects. Most replacement effects use the word “instead” to indicate what events will be replaced with other events and use the word “skip” to indicate what events, steps, phases, or turns will be replaced with nothing.

419.1b Effects that read “[This permanent] comes into play with . . . ,” “As [this permanent] comes into play . . . ,” or “[This permanent] comes into play as . . . ” are replacement effects.

419.1c Continuous effects that read “[This permanent] comes into play . . .” or “[Objects] come into play . . .” are replacement effects.

419.1d Effects that use the word “prevent” are prevention effects. Prevention effects use “prevent” to indicate what events will not occur.

419.1e Effects that read “As [this permanent] is turned face up . . . ,” are replacement effects.

419.2. Replacement and prevention effects apply continuously as events happen-they aren’t locked in ahead of time.

419.3. There are no special restrictions on playing a spell or ability that generates a replacement or prevention effect. Such effects last until they’re used up or their duration has expired.

419.4. Replacement or prevention effects must exist before the appropriate event occurs-they can’t “go back in time” and change something that’s already happened. Usually spells and abilities that generate these effects are played in response to whatever would produce the event and thus resolve before that event would occur.

Example: A player can play a regeneration ability in response to a spell that would destroy a creature he or she controls.

419.5. If an event is prevented or replaced, it never happens. A modified event occurs instead, which may in turn trigger abilities. Note that the modified event may contain instructions that can’t be carried out, in which case the player simply ignores the impossible instruction.

419.5a If a source would deal 0 damage, it does not deal damage at all. That means abilities that trigger on damage being dealt won’t trigger. It also means that replacement effects that increase damage dealt have no event to replace, so they have no effect.

419.5b Some abilities read, “you may [X]. If you do, [Y].” An “if you do” clause that follows a “you may [X]” clause refers to choosing to do the event X, regardless of what events actually occur as a result of that decision. If X is replaced entirely or in part by a different event, the “if you do” clause refers to the event that replaced X.

419.6. Replacement Effects

419.6a A replacement effect doesn’t invoke itself repeatedly and gets only one opportunity for each event.