Peer into the Abyss

Target player draws cards equal to half the number of cards in their library and loses half their life. Round up each time.

Necrologia

Cast this spell only during your end step.
As an additional cost to cast this spell, pay X life.
Draw X cards.

Return target spell to its owner's hand.
Draw a card.

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.