Rin and Seri, Inseparable (Buy-A-Box) [Core Set 2021] MON000-CF but it is necessary

but it is necessary

sacrifice Draco unless you pay {10}

create X 1/1 Sand Warrior creature tokens that are red

or planeswalker card from among them and put it into your hand

then an opponent gains control of them

Rin and Seri, Inseparable (Buy-A-Box) [Core Set 2021] MON000-CF but it is necessarySet: Core Set 2021 Type: Legendary Creature Dog Cat Rarity: Mythic Cost: {1}{R}{G}{W} Whenever you cast a Dog spell, create a 1 1 green Cat creature token. Whenever you cast a Cat spell, create a 1 1 white Dog creature token. {R}{G}{W}, {T}: Rin and Seri, Inseparable deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.