Your life total is higher than or equal to an opponent's.
({1} magic symbol) available.
Steps
Activate Disciple of Griselbrand by paying ({1} magic symbol) and sacrificing Soul of Eternity, causing you to gain life equal to its toughness.
Vito triggers, causing target opponent whose lifetotal is less than or equal to Soul of Eternity's toughness to lose life equal to the life you gained.
The opponent loses the game due to having zero or less life.