Samut, Tyrant of Naktamun is a rare Legendary Creature — Human Wizard card from Reality Fracture (FRA), collector number 302. Current market price: $5.99 (foil $26.10), TCGplayer market prices via Scryfall.
Instant and sorcery spells you control have split second. (As long as a spell with split second is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)