418.5. Interaction of Continuous Effects
418.5a The values of an object’s characteristics are determined by starting with the actual object, then applying continuous effects in a series of layers in the following order: (1) copy effects (see rule 503, “Copying Objects”); (2) control-changing effects; (3) text-changing effects; (4) type-, subtype-, and supertype-changing effects; (5) all other continuous effects, except those that change power and/or toughness; and (6) power– and/or toughness-changing effects.
Inside each layer from 1 through 5, apply effects from characteristic-setting abilities first, then all other effects. Inside layer 6, apply effects in a series of sublayers in the following order: (6a) effects from characteristic- setting abilities; (6b) all other effects not specifically applied in 6c, 6d, or 6e; (6c) changes from counters; (6d) effects from static abilities that modify power and/or toughness but don’t set power and/or toughness to a specific number or value; and (6e) effects that switch a creature’s power and toughness. See also the rules for timestamp order and dependency (rules 418.5b-418.5g).
Example: Crusade is an enchantment that reads “White creatures get +1/+1.” Crusade and a 2/2 black creature are in play. If an effect then turns the creature white, it gets +1/+1 from Crusade, becoming 3/3. If the creature’s color is later changed to red, Crusade’s effect stops applying to it, and it will return to being a 2/2.
Example: Gray Ogre, a 2/2 creature, is in play. An effect puts a +1/+1 counter on it, making it 3/3. An effect that says “Target creature gets +4/+4 until end of turn” is applied to it, making it 7/7. An enchantment that says “Creatures you control get +0/+2” enters play, making it a 7/9. An effect that says “Target creature becomes 0/1 until end of turn” is applied to it, making it a 1/4 (0/1, plus +1/+1 from the counter, plus +0/+2 from the enchantment).
Example: Svogthos, the Restless Tomb, is in play. An effect that says “Until end of turn, target land becomes a 3/3 creature that’s still a land” is applied to it. An effect that says “Target creature gets +1/+1 until end of turn” is applied to it, making it a 4/4 land creature. Then you activate Svogthos’s ability (“Until end of turn, Svogthos, the Restless Tomb becomes a black and green Plant Zombie creature with ‘This creature’s power and toughness are each equal to the number of creature cards in your graveyard.’ It’s still a land.”) while you have ten creature cards in your graveyard. It becomes a 10/10 land creature. If a creature card enters or leaves your graveyard, Svogthos’s power and toughness will be modified accordingly. If the first effect is applied to it again, it will become a 3/3 land creature again.
418.5b If an effect should be applied in different layers, the parts of the effect each apply in their appropriate layers. If an effect starts to apply in one layer, it will continue to be applied to the same set of objects in each other applicable layer, even if the ability generating the effect is removed during this process.
Example: An effect that reads “Wild Mongrel gets +1/+1 and becomes the color of your choice until end of turn” is both a power– and toughness-changing effect and an “other” kind of effect. The “becomes the color of your choice” part is applied in layer 5, and then the “gets +1/+1” part is applied in layer 6.
Example: Grab the Reins has an effect that reads “Until end of turn, you gain control of target creature and it gains haste.” This is both a control-changing effect and an “other” effect. The “you gain control” part is applied in layer 2, and then the “it gains haste” part is applied in layer 5.
Example: An effect that reads “All noncreature artifacts become 2/2 artifact creatures until end of turn” is both a type-changing effect and a power– and toughness-setting effect. The type-changing effect is applied to all noncreature artifacts in layer 4 and the power– and toughness-setting effect is applied to those same permanents in layer 6, even though those permanents aren’t noncreature artifacts by then.
418.5c An effect is said to “depend on” another if (a) it’s applied in the same layer (and, if applicable, sublayer) as the other effect (see rule 418.5a) and (b) applying the other would change the text or the existence of the first effect, what it applies to, or what it does to any of the things it applies to. Otherwise, the effect is considered to be independent of the other effect.
418.5d An effect dependent on one or more other effects waits to apply until just after all of those effects have been applied, even if this causes a characteristic-setting ability to apply after another effect. If multiple dependent effects would apply simultaneously in this way, they’re applied in “timestamp order” relative to each other. If several dependent effects form a dependency loop, then this rule is ignored and the effects in the dependency loop are applied in timestamp order.
418.5e An object’s timestamp is the time it entered the zone it’s currently in, with three exceptions: (a) If two or more objects enter a zone (or zones) simultaneously, the active player determines their timestamp order at the time they enter that zone. (b) Whenever an Aura or Equipment becomes attached to a permanent, the Aura or Equipment receives a new timestamp. (c) Permanents that phase in keep the same timestamps they had when they phased out.
418.5f A continuous effect generated by a static ability has the same timestamp as the object the static ability is on, or the timestamp of the effect that created the ability, whichever is later.
418.5g A continuous effect generated by the resolution of a spell or ability receives a timestamp at the time it’s created.
418.5h One continuous effect can override another. Sometimes the results of one effect determine whether another effect applies or what another effect does.
Example: Two Auras are played on the same creature: “Enchanted creature gains flying” and “Enchanted creature loses flying.” Neither of these depends on the other, since nothing changes what they affect or what they’re doing to it. Applying them in timestamp order means the one that was generated last “wins.” It’s irrelevant whether an effect is temporary (such as “Target creature loses flying until end of turn”) or global
