Rule 613.8

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 enchanting the same creature: one that says "Enchanted creature gains flying" and one that says "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 (such as "All creatures lose flying"). Example: One effect reads, "White creatures get +1/+1," and another reads, "Enchanted creature is white." The enchanted creature gets +1/+1 from the first effect, regardless of its previous color.

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