Demonlord Belzenlok
Legendary Creature — Elder Demon
Flying, trample
When Demonlord Belzenlok enters the battlefield, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's converted mana cost is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.
Illustrated by
Dominaria#86MythicEnglishLegality
Rulings
Once the triggered ability resolves, the ability will continue until you either exile a nonland card with converted mana cost 3 or less or fail to exile any nonland cards while performing the process. You can’t choose to stop receiving the blessings of Demonlord Belzenlok any sooner.
Land cards exiled this way remain exiled.
Demonlord Belzenlok’s ability causes it to deal an amount of damage to you all at once; it doesn’t deal 1 damage multiple times.
If the mana cost of the nonland card includes 
, X is considered to be 0.
If the nonland card doesn’t have a mana cost, its converted mana cost is 0.
The converted mana cost of a split card, such as a card with aftermath from the Amonkhet block, is equal to the combined mana cost of its two halves.