Day and night

Dayman and Nightman are designations that a game of Magic: The Gathering can have. These were introduced in Innistrad: Midnight Hunt.

Description

When the game starts, it's neither day nor night. In most games, it will become day first. The most common way that will happen is if a permanent with daybound appears on the battlefield. In some uncommon cases, it may become night first because a permanent with nightbound appears first.

Once it's day or night, the game will be exactly one of those designations, day or night, going back and forth until the game ends. It can never return to being neither. And the whole game is either day or night. It's not a per player thing.

If it's day, each double-faced card with daybound and nightbound will enter the battlefield with its daybound face up. If it's night, each of them will enter nightbound face up. Note that this doesn't affect spells on the stack.

There are two ways for the game's day/night designation to change. If it's day as a turn begins, and the previous turn's active player didn't cast a spell last turn, it becomes night. Similarly, if it's night as a turn begins, if the previous turn's active player cast two or more spells last turn, it becomes day. To help everyone keep track of day and night, a helper card that reminds you of these rules. Another way the day/night designation can change is when cards have effects that just say it becomes day or night. This can happen at any point in the turn when the effect says so.

As it becomes day, all double-faced cards with nightbound transform to their daybound faces. As it becomes night, all double-faced cards with daybound transform to their nightbound faces. In other words, these double-faced cards should always be in sync, no matter who controls them. What's more, permanents with daybound and nightbound can't transform any other way.

Rules

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

Day

Along with night, a designation the game can have. See rule 727, “Day and Night,” and rule 702.145, “Daybound and Nightbound.”

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

Night

Along with day, a designation the game can have. See rule 728, “Day and Night,” and rule 702.145, “Daybound and Nightbound.”

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

• 728. Day and Night
  • 728.1. Day and night are designations that the game itself can have. The game starts with neither designation. “It becomes day” and “it becomes night” refer to the game gaining the day or night designation. It can become day or night through the daybound and nightbound keyword abilities (see rule 702.145). Other effects can also make it day or night. Once it has become day or night, the game will have exactly one of those designations from that point forward.
    • 728.1a The phrases “day becomes night” and “night becomes day” refer to the game losing the first designation and gaining the second one.
  • 728.2. As the second part of the untap step, the game checks the previous turn to see if the game’s day/night designation should change. See rule 502, “Untap Step.”
    • 728.2a If it’s day and the previous turn’s active player didn’t cast any spells during that turn, it becomes night. Multiplayer games using the shared team turns option (see rule 805) use a modified rule: if it’s day and no player from the previous turn’s active team cast a spell during that turn, it becomes night.
    • 728.2b If it’s night, and previous turn’s active player cast two or more spells during the previous turn, it becomes day. Multiplayer games using the shared team turns option (see rule 805) use a modified rule: if it’s night and any player from the previous turn’s active team cast two or more spells during that turn, it becomes day.
    • 728.2c If it’s neither day nor night, this check doesn’t happen and it remains neither.

Helper card