Graveblade Marauder

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever this creature deals combat damage to a player, that player loses life equal to the number of creature cards in your graveyard.

Foundations Jumpstart

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever Graveblade Marauder deals combat damage to a player, that player loses life equal to the number of creature cards in your graveyard.

Jumpstart 2022

Deathtouch
Whenever Graveblade Marauder deals combat damage to a player, that player loses life equal to the number of creature cards in your graveyard.

Double Masters 2022

New Capenna Commander

Magic Origins

Count the number of creature cards in your graveyard as the ability resolves to determine how much life is lost. Notably, this could include any other creature you owned that died in combat, and perhaps even Graveblade Marauder itself.