Marina Vendrell's Grimoire | Sheoldred, the Apocalypse

Cards

Cast
Marina Vendrell's Grimoire by paying ({5} magic symbol) ({U} magic symbol) .
When
Marina Vendrell's Grimoire enters the battlefield, its first ability triggers, causing you to draw five cards.
Sheoldred's first ability triggers five times.
Resolve the first
Sheoldred trigger, causing you to gain 2 life.
Marina Vendrell's Grimoire's second ability triggers, causing you to draw two cards.
Sheoldred's first ability triggers twice.
Repeat from step 4.

This combo will result in you eventually drawing from an empty library, thus losing the game. It is highly recommended to have a way to stop the combo at instant speed or to otherwise stop yourself from losing the game.