Autumnal Gloom

{B}: Mill a card.
Delirium — At the beginning of your end step, if there are four or more card types among cards in your graveyard, transform Autumnal Gloom.

"When the leaves fall and the nights grow cold, look elsewhere for firewood."
—Ola of Lambholt

Ancient of the Equinox

Autumnal Gloom // Ancient of the Equinox

{B}: Mill a card.
Delirium — At the beginning of your end step, if there are four or more card types among cards in your graveyard, transform Autumnal Gloom. 

 Trample, hexproof

Autumnal Gloom // Ancient of the Equinox

Enchantment // Creature — Treefolk