Song of Stupefaction
From The Lost Caverns of Ixalan set
Song of Stupefaction
Enchantment — Aura
Enchant creature or Vehicle
When this Aura enters, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Fathomless descent — Enchanted permanent gets -X/-0, where X is the number of permanent cards in your graveyard.