413.2c If an effect offers any choices other than choices already made as part of playing the spell or ability, the player announces these while applying the effect. The player can’t choose an option that’s illegal or impossible. (For example, a player can’t avoid the consequences of not taking an optional action if he or she can’t meet all the immediate requirements of that action.) Drawing a card is never considered an impossible action, even if there are no cards in the affected player's library.

Example: A spell’s instruction reads, “You may sacrifice a creature. If you don’t, you lose 4 life.” A player who controls no creatures can’t choose the sacrifice option.

413.2d Some spells and abilities have multiple steps or actions, denoted by separate sentences or clauses. In these cases, the choices for the first action are made in APNAP order, and then the first action is processed simultaneously. Then the choices for the second action are made in APNAP order, and then that action is processed simultaneously, and so on. See rule 103.4.

413.2e If an effect gives a player the option to pay mana, he or she may play mana abilities before taking that action. If an effect specifically instructs or allows a player to play a spell during resolution, he or she does so by putting that spell on top of the stack, then continuing to play it by following the steps in rules 409.1a-i (except no player receives priority after it’s played). The currently resolving spell or ability then continues to resolve, which may include playing other spells this way. No other spells or abilities can normally be played during resolution.

413.2f If an effect requires information from the game (such as the number of creatures in play), the answer is determined only once, when the effect is applied. The effect uses the current information of a specific permanent if that permanent is still in play, or of a specific card in the stated zone; otherwise, the effect uses the last known information the object had before leaving that zone. There are two exceptions. If an effect deals damage divided among some number of creatures or players, the amount and division were determined as the spell or ability was put into the stack; see rule 402.6. Also, static abilities can’t use last known information; see rule 412.5. If the ability text states that an object does something, it’s the object as it exists (or most recently existed) that does it, not the ability.

413.2g An effect that refers to characteristics of an object checks only for the value of the specified characteristics, regardless of any related ones the object may also have.

Example: An effect that reads “Destroy all black creatures” destroys a white-and-black creature, but one that reads “Destroy all nonblack creatures” doesn’t.

413.2h A spell is put into play from the stack under the control of the spell’s controller (for permanents) or is put into its owner’s graveyard from the stack (for instants and sorceries) as the final step of the spell’s resolution.

413.2i If an effect could result in a tie, the text of the spell or ability that created the effect will specify what to do in the event of a tie. The Magic game has no default for ties.

414.1. To counter a spell is to move the spell from the stack to its owner’s graveyard. Countering an ability removes it from the stack. Spells and abilities that are countered don’t resolve and none of their effects occur.

414.2. The player who played the countered spell or ability doesn’t get a “refund” of any costs that were paid.

415.1. An instant or sorcery spell is targeted if the text that will be followed when it resolves uses the phrase “target [something],” where the “something” is a phrase that describes an object, player, or zone. (If an activated or triggered ability of an instant or sorcery uses the word target, that ability is targeted, but the spell is not.)

Example: A sorcery card has the ability “When you cycle this card, target creature gets -1/-1 until end of turn.” This triggered ability is targeted, but that doesn’t make the card it’s on targeted.

415.2. An activated or triggered ability is targeted if it uses the phrase “target [something],” where the “something” is a phrase that describes an object, player, or zone.

415.3. Aura spells are always targeted. An Aura’s target is specified by its enchant keyword ability (see rule 502.45, “Enchant”). An Aura permanent doesn’t target anything; only the spell is targeted. An activated or triggered ability of an Aura permanent can be targeted.

Neither Equipment spells nor Equipment permanents target anything. The equip ability is targeted; see rule 502.33, “Equip.” An activated or triggered ability of an Equipment permanent can be targeted.

415.4. Spells and abilities that can have zero or more targets are targeted only if one or more targets have been chosen for them.

415.5. Only permanents are legal targets for spells and abilities, unless a spell or ability (a) specifies that it can target an object in another zone or a player or (b) targets an object that can’t exist in the in-play zone, such as a spell or ability.

415.6. A spell or ability on the stack is an illegal target for itself.

415.7. Changing Targets

415.7a The target of a spell or ability can change only to another legal target. If the target can’t be changed to another legal target, the original target is unchanged.

415.7b Modal spells and abilities may have different targeting requirements for each mode. Changing a spell or ability’s target can’t change its mode.

415.7c The word “you” in an object’s text isn’t a target.

416.1. When a spell or ability resolves, it may create one or more one-shot or continuous effects. Static abilities may create one or more continuous effects. Some effects are replacement effects or prevention effects. State-based effects are not created by spells or abilities; they are generated by specific rules of the game.

416.2. Effects apply only to permanents unless the instruction’s text states otherwise or they clearly can apply only to objects in one or more other zones.

Example: An effect that changes all lands into creatures won’t alter land cards in players’ graveyards. But an effect that says spells cost more to play will apply only to spells on the stack, since a spell is always on the stack while you are playing it.

416.3. If an effect attempts to do something impossible, it does only as much as possible.

Example: If a player is holding only one card, an effect that reads “Discard two cards” causes him or her to discard only that card. If an effect moves cards out of the library (as opposed to drawing), it moves as many as possible.