Turn-based action

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

Turn-Based Actions

Game actions that happen automatically when certain steps or phases begin, or when each step or phase ends. See rule 703, “Turn-Based Actions.”

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

• 703. Turn-Based Actions
  • 703.1. Turn-based actions are game actions that happen automatically when certain steps or phases begin, or when each step and phase ends. Turn-based actions don’t use the stack.
    • 703.1a Abilities that watch for a specified step or phase to begin are triggered abilities, not turn-based actions. (See rule 603, “Handling Triggered Abilities.”)
  • 703.2. Turn-based actions are not controlled by any player.
  • 703.3. Whenever a step or phase begins, if it’s a step or phase that has any turn-based action associated with it, those turn-based actions are automatically dealt with first. This happens before state-based actions are checked, before triggered abilities are put on the stack, and before players receive priority.
  • 703.4. The turn-based actions are as follows:
    • 703.4a Immediately after the untap step begins, all phased-in permanents with phasing that the active player controls phase out, and all phased-out permanents that the active player controlled when they phased out phase in. This all happens simultaneously. See rule 502.1.
    • 703.4b Immediately after the phasing action has been completed during the untap step, if the game has either the day or night designation, it checks to see whether that designation should change. If it’s neither day nor night, this check doesn’t happen. See rule 502.2.
    • 703.4c Immediately after the game checks to see if its day or night designation should change during the untap step or, if the game doesn’t have a day or night designation, immediately after the phasing action has been completed during the untap step, the active player determines which permanents they control will untap. Then they untap them all simultaneously. See rule 502.3.
    • 703.4d Immediately after the draw step begins, the active player draws a card. See rule 504.1.
    • 703.4e In an Archenemy game (see rule 904), immediately after the archenemy’s precombat main phase begins, that player sets the top card of their scheme deck in motion. See rule 701.25.
    • 703.4f Immediately after a player’s precombat main phase begins, that player puts a lore counter on each Saga enchantment they control. In an Archenemy game, this happens after the archenemy’s scheme action. See rule 714, “Saga Cards.”
    • 703.4g Immediately after the action of placing lore counters has been completed, if the active player controls any Attractions, that player rolls to visit their Attractions. See rule 701.49, “Roll to Visit Your Attractions.”
    • 703.4h Immediately after the beginning of combat step begins, if the game being played is a multiplayer game in which the active player’s opponents don’t all automatically become defending players, the active player chooses one of their opponents. That player becomes the defending player. See rule 507.1.
    • 703.4i Immediately after the declare attackers step begins, the active player declares attackers. See rule 508.1.
    • 703.4j Immediately after the declare blockers step begins, the defending player declares blockers. See rule 509.1.
    • 703.4k Immediately after blockers have been declared during the declare blockers step, for each attacking creature that’s become blocked by multiple creatures, the active player announces the damage assignment order among the blocking creatures. See rule 509.2.
    • 703.4m Immediately after the active player has announced damage assignment orders (if necessary) during the declare blockers step, for each creature that’s blocking multiple creatures, the defending player announces the damage assignment order among the attacking creatures. See rule 509.3.
    • 703.4n Immediately after the combat damage step begins, each player in APNAP order announces how each attacking or blocking creature they control assigns its combat damage. See rule 510.1.
    • 703.4p Immediately after combat damage has been assigned during the combat damage step, all combat damage is dealt simultaneously. See rule 510.2.
    • 703.4q Immediately after the cleanup step begins, if the active player’s hand contains more cards than their maximum hand size (normally seven), they discard enough cards to reduce their hand size to that number. See rule 514.1.
    • 703.4r Immediately after the active player has discarded cards (if necessary) during the cleanup step, all damage is removed from permanents and all “until end of turn” and “this turn” effects end. These actions happen simultaneously. See rule 514.2.
    • 703.4s When each step or phase ends, any unused mana left in a player’s mana pool empties. See rule 500.4.