The Winged Dragon of Ra

Summon (Your creatures can help cast this spell.
Each creature you sacrifice while casting this spell
pays for {1} or one mana of the creature's color.)
Split second
When The Winged Dragon of Ra enters the battlefield, if you didn't cast it from your hand, sacrifice it at the beginning of the next end step,
then you may pay X life. The Winged Dragon of
Ra's power and toughness are each equal to X.
Pay 3 life: Destroy target creature.