One-shot effect

One-shot effects are effects which do not last for an extended period of time.

Rules

From the glossary of the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

One-Shot Effect

An effect that does something just once and doesn’t have a duration. See rule 610, “One-Shot Effects.” See also Continuous Effects.

From the Comprehensive Rules (June 7, 2024—Modern Horizons 3)

• 610. One-Shot Effects
  • 610.1. A one-shot effect does something just once and doesn’t have a duration. Examples include dealing damage, destroying a permanent, creating a token, and moving an object from one zone to another.
  • 610.2. Some one-shot effects create a delayed triggered ability, which instructs a player to do something later in the game (usually at a specific time) rather than as the spell or ability that’s creating the one-shot effect resolves. See rule 603.7.
  • 610.3. Some one-shot effects cause an object to change zones “until” a specified event occurs. A second one-shot effect is created immediately after the specified event. This second one-shot effect returns the object to its previous zone.
    • 610.3a If a resolving spell or activated ability creates the initial one-shot effect that causes the object to change zones, and the specified event has already occurred before that one-shot effect would occur but after that spell or ability was put onto the stack, the object doesn’t move.
    • 610.3b If a resolving triggered ability creates the initial one-shot effect that causes the object to change zones, and the specified event has already occurred before that one-shot effect would occur but after that ability triggered, the object doesn’t move.
    • 610.3c An object returned to the battlefield this way returns under its owner’s control unless otherwise specified.
    • 610.3d If multiple one-shot effects are created this way immediately after one or more simultaneous events, those one-shot effects are also simultaneous.

      Example: Two Banisher Priests have each exiled a card. All creatures are destroyed at the same time by Day of Judgment. The two exiled cards are returned to the battlefield at the same time.

  • 610.4. Some one-shot effects cause a permanent to phase out “until” a specified event occurs. A second one-shot effect is created immediately after the specified event. This second one-shot effect causes the permanent to phase in.
    • 610.4a A permanent phased out this way doesn’t phase in as a result of the turn-based action during a player’s untap step (see rule 502.1). Other effects may cause it to phase in. If a permanent phased out this way phases in due to another effect, the second one-shot effect doesn’t happen, even if that permanent has phased out again.
    • 610.4b If a resolving spell or activated ability creates the initial one-shot effect that causes the permanent to phase out, and the specified event has already occurred before that one-shot effect would occur but after that spell or ability was put onto the stack, the permanent doesn’t phase out.
    • 610.4c If a resolving triggered ability creates the initial one-shot effect that causes the permanent to phase out, and the specified event has already occurred before that one-shot effect would occur but after that ability triggered, the permanent doesn’t phase out.
    • 610.4d If multiple one-shot effects are created this way immediately after one or more simultaneous events, those one-shot effects are also simultaneous.

Examples

Some examples of one-shot effects include the following:

• Direct damage or burn, characterized by the card Lightning Bolt
• Lifegain, characterized by Healing Salve
• Land destruction, as represented by cards such as Sinkhole
• Fast mana sources, such as Dark Ritual or Seething Song
• Creature removal in the forms of Terror and Swords to Plowshares

Cantrips

Some of these one-shot effects also "replace" themselves in the form of cantrips. Often, a card will have a slightly heightened mana cost in exchange for the phrase "Draw a card" in the spell's text box. This allows little to no loss, and even the possibility of gaining card advantage and tempo.

Slowtrips

Slowtrips are merely delayed cantrips that were introduced in Ice Age and Coldsnap. While they do not have the "immediate" effect of a cantrip, they still allow the card being played to replace itself. The text associated with a slowtrip is "Draw a card at the beginning of the next turn's upkeep."