611.1 A continuous effect modifies characteristics of objects, modifies control of objects, or affects players or the rules of the game, for a fixed or indefinite period.
611.2a A continuous effect generated by the resolution of a spell or ability lasts as long as stated by the spell or ability creating it (such as “until end of turn”). If no duration is stated, it lasts until the end of the game.
611.2b Some continuous effects generated by the resolution of a spell or ability have durations worded “for as long as . . . .” If the “for as long as” duration never starts, the effect does nothing. Similarly, if that duration ends before the moment the effect would first be applied and doesn’t begin again during that spell or ability’s resolution, the effect does nothing. It doesn’t start and immediately stop again, and it doesn’t last forever.
611.2c If a continuous effect generated by the resolution of a spell or ability modifies the characteristics or changes the controller of any objects, the set of objects it affects is determined when that continuous effect begins. After that point, the set won’t change. (Note that this works differently than a continuous effect from a static ability.) A continuous effect generated by the resolution of a spell or ability that doesn’t modify the characteristics or change the controller of any objects modifies the rules of the game, so it can affect objects that weren’t affected when that continuous effect began. If a single continuous effect has parts that modify the characteristics or changes the controller of any objects and other parts that don’t, the set of objects each part applies to is determined independently.
611.2d If a resolving spell or ability that creates a continuous effect contains a variable such as X, the value of that variable is determined only once, on resolution. See rule 608.2h.
611.2e If a resolving spell or ability both puts a nontoken permanent onto the battlefield and creates a continuous effect stating that the permanent “is [characteristic],” that it “has [characteristic],” or that it doesn’t have a particular characteristic, that continuous effect applies simultaneously with the permanent entering the battlefield. This characteristic is usually a color or a creature type. If the continuous effect says the permanent “becomes [characteristic]” or “gains [an ability],” that effect applies after the permanent is on the battlefield.
611.2f Some spells and abilities generate a continuous effect that modifies the characteristics of the next spell a player casts, the next spell that fulfills certain conditions a player casts during some duration, or similar. These effects do not begin immediately. Rather, they begin to apply at the time that player next puts an appropriate spell on the stack, and they apply to that spell. See rule 601.2a.
611.3c Continuous effects that modify characteristics of permanents do so simultaneously with the permanent entering the battlefield. They don’t wait until the permanent is on the battlefield and then change it. Because such effects apply as the permanent enters the battlefield, they are applied before determining whether the permanent will cause an ability to trigger when it enters the battlefield.
611.3d Continuous effects from static abilities may allow a player to play a land or cast a permanent spell, or may grant an ability to a permanent spell or card that allows it to be cast. If the effect also grants that object an ability that functions only on the battlefield, that ability lasts as long as stated by the effect granting that permission or ability. If no duration is stated, it lasts until the end of the game. This is an exception to rules 611.3a–b.