Underground Sea

Griselbrand

Flying, lifelink
Pay 7 life: Draw seven cards.

Avacyn, Angel of Hope

Flying, vigilance, indestructible
Other permanents you control have indestructible.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Animate Dead

Enchant creature card in a graveyard
When Animate Dead enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with Animate Dead." Return enchanted creature card to the battlefield under your control and attach Animate Dead to it. When Animate Dead leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Entomb

Search your library for a card, put that card into your graveyard, then shuffle.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Serra's Emissary

Flying
As Serra's Emissary enters, choose a card type.
You and creatures you control have protection from the chosen card type.

Thoughtseize

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Scrubland

Unmask

You may exile a black card from your hand rather than pay this spell's mana cost.
Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Atraxa, Grand Unifier

Flying, vigilance, deathtouch, lifelink
When Atraxa, Grand Unifier enters, reveal the top ten cards of your library. For each card type, you may put a card of that type from among the revealed cards into your hand. Put the rest on the bottom of your library in a random order. (Artifact, battle, creature, enchantment, instant, land, planeswalker, and sorcery are card types.)

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Dark Ritual

Verdant Catacombs

{T}, Pay 1 life, Sacrifice Verdant Catacombs: Search your library for a Swamp or Forest card, put it onto the battlefield, then shuffle.

Swamp

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Bloodstained Mire

{T}, Pay 1 life, Sacrifice Bloodstained Mire: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Badlands

Grief

Menace
When Grief enters, target opponent reveals their hand. You choose a nonland card from it. That player discards that card.
Evoke—Exile a black card from your hand.

Toxrill, the Corrosive

At the beginning of each end step, put a slime counter on each creature you don't control.
Creatures you don't control get -1/-1 for each slime counter on them.
Whenever a creature you don't control with a slime counter on it dies, create a 1/1 black Slug creature token.
{U}{B}, Sacrifice a Slug: Draw a card.

Archon of Cruelty

Flying
Whenever Archon of Cruelty enters or attacks, target opponent sacrifices a creature or planeswalker of their choice, discards a card, and loses 3 life. You draw a card and gain 3 life.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.