Split Second

Split second is a keyword ability that was introduced in the Time Spiral block.

From the Comprehensive Rules (November 8, 2024—Edge of Eternities)

• 702.61. Split Second
  • 702.61a Split second is a static ability that functions only while the spell with split second is on the stack. “Split second” means “As long as this spell is on the stack, players can’t cast other spells or activate abilities that aren’t mana abilities.”
  • 702.61b Players may activate mana abilities and take special actions while a spell with split second is on the stack. Triggered abilities trigger and are put on the stack as normal while a spell with split second is on the stack.
  • 702.61c Multiple instances of split second on the same spell are redundant.
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• Players still get priority while a card with split second is on the stack.
• Split second doesn’t prevent players from activating mana abilities.
• Split second doesn’t prevent triggered abilities from triggering. If one does, its controller puts it on the stack and, if applicable, chooses targets for it. Those abilities will resolve as normal.
• Split second doesn’t prevent players from performing special actions. Most notably, players may turn face-down creatures face-up while a spell with split second is on the stack. For example, if Sudden Death is targeting a creature you control, you may flip up a Willbender to change the target of Sudden Death to another creature.
• Split second does not prevent the spell from being countered by triggered abilities. One such example is Voidmage Apprentice. Decree of Silence can also counter cards with split second.
• Split second won’t affect spells and abilities that are already on the stack.
• If the resolution of a triggered ability involves casting a spell, that part of the effect won’t work if a spell with split second is on the stack.