The Lost Caverns of Ixalan Promos

Creature — Spirit Horror

When this creature enters, surveil 2. Then for each card you put on top of your library, you draw a card and you lose 3 life.
Descend 8 — Whenever you draw a card, if there are eight or more permanent cards in your graveyard, target opponent loses 1 life and you gain 1 life.

Starving Revenant

The Lost Caverns of Ixalan

Creature — Spirit Advisor

Flying
Descend 4 — When this creature enters, if there are four or more permanent cards in your graveyard, return up to one target nonland permanent other than this creature to its owner's hand.

Council of Echoes

Creature — Spirit Cleric

When this creature enters, draw a card.
Descend 4 — This creature has flying as long as there are four or more permanent cards in your graveyard.

Didact Echo

Legendary Artifact Land

(Transforms from The Everflowing Well.)
{T}: Add {U}.
Whenever you cast a permanent spell using mana produced by The Myriad Pools, up to one other target permanent you control becomes a copy of that spell until end of turn.

The Myriad Pools

Legendary Artifact

When The Everflowing Well enters, mill two cards, then draw two cards.
Descend 8 — At the beginning of your upkeep, if there are eight or more permanent cards in your graveyard, transform The Everflowing Well.

The Everflowing Well

The Lost Caverns of Ixalan Commander

Sorcery

Descend 8 — When you cast this spell, if there are eight or more permanent cards in your graveyard, copy this spell twice. You may choose new targets for the copies.
Return target permanent card from your graveyard to your hand. Exile Bygone Marvels.

Bygone Marvels

Creature — Salamander Wurm

Descend 4 — This creature gets +2/+0 as long as there are four or more permanent cards in your graveyard.

Frilled Cave-Wurm

Legendary Creature — Spirit God

Descend 8 — The Ancient One can't attack or block unless there are eight or more permanent cards in your graveyard.
{2}{U}{B}: Draw a card, then discard a card. When you discard a card this way, target player mills cards equal to its mana value.

The Ancient One

Artifact — Vehicle

Vigilance
Descend 8 — This Vehicle can't be blocked as long as there are eight or more permanent cards in your graveyard.
Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

Watertight Gondola

Artifact

{T}: Mill a card. (Put the top card of your library into your graveyard.)
Craft with Island {3}{U} ({3}{U}, Exile this artifact, Exile an Island you control or an Island card from your graveyard: Return this card transformed under its owner's control. Craft only as a sorcery.)

Waterlogged Hulk

Creature — Vampire Spirit

Descend 4 — As long as there are four or more permanent cards in your graveyard, this creature gets +1/+1 and has lifelink.

Echo of Dusk

Descend 8 — Choose one. If there are eight or more permanent cards in your graveyard as you cast this spell, choose one or more instead.
• Return target nonland permanent to its owner's hand.
• Target opponent discards a card.
• Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Wail of the Forgotten

Instant

Target creature gets -5/-5 until end of turn.
Descend 4 — That creature gets -10/-10 until end of turn instead if there are four or more permanent cards in your graveyard.

Join the Dead

Creature — Insect Horror

Deathtouch
Descend 4 — Whenever this creature attacks, if there are four or more permanent cards in your graveyard, you draw a card and you lose 1 life.

Stinging Cave Crawler

Creature — Capybara

Descend 4 — This creature gets +3/+0 as long as there are four or more permanent cards in your graveyard.

Basking Capybara

Creature — Raccoon

Descend 4 — When this creature enters, if there are four or more permanent cards in your graveyard, return target permanent card from your graveyard to your hand.

Coati Scavenger

Creature — Cat Warrior

Trample
Descend 4 — Whenever this creature attacks, if there are four or more permanent cards in your graveyard, put a +1/+1 counter on target creature.

Malamet Veteran

Legendary Creature — Fungus

Descend 4 — As long as there are four or more permanent cards in your graveyard, Akawalli gets +2/+2 and has trample.
Descend 8 — As long as there are eight or more permanent cards in your graveyard, Akawalli gets an additional +2/+2 and can't be blocked by more than one creature.

Akawalli, the Seething Tower

Legendary Creature — Skeleton Horror

Vigilance, menace
Descend 8 — {4}{U}{B}: Return this card from your graveyard to the battlefield with a finality counter on it. Activate only if there are eight or more permanent cards in your graveyard and only as a sorcery. (If a creature with a finality counter on it would die, exile it instead.)