Mirko Vosk, Mind Drinker — ruling 1

If the player has fewer than four land cards in their library, all cards from that library will be revealed and put into that player's graveyard.

Mirko Vosk, Mind Drinker : règles, fonctionnement et interactions (MTG)

Mirko Vosk, Mind Drinker is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Flying Whenever Mirko Vosk deals combat damage to a player, that player reveals cards from the top of their library until they reveal four land cards, then puts those cards into their graveyard.

How it works : Mirko Vosk, Mind Drinker

Original English text — Wizards of the Coast / Scryfall

#1April 15, 2013· Wizards of the Coast
If the player has fewer than four land cards in their library, all cards from that library will be revealed and put into that player's graveyard.
No other card is named in this ruling.