Homicidal Seclusion

As long as you control exactly one creature, that creature gets +3/+1 and has lifelink.

Bottomless Vault

Bottomless Vault enters tapped.
You may choose not to untap Bottomless Vault during your untap step.
At the beginning of your upkeep, if Bottomless Vault is tapped, put a storage counter on it.
{T}, Remove any number of storage counters from Bottomless Vault: Add {B} for each storage counter removed this way.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Swamp

Terrain Generator

{T}: Add {C}.
{2}, {T}: You may put a basic land card from your hand onto the battlefield tapped.

Sibsig Muckdraggers

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
When Sibsig Muckdraggers enters, return target creature card from your graveyard to your hand.

Skirge Familiar

Corpsehatch

Destroy target nonblack creature. Create two 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this creature: Add {C}."

Contract Killing

Destroy target creature. Create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Grim Poppet

Grim Poppet enters with three -1/-1 counters on it.
Remove a -1/-1 counter from Grim Poppet: Put a -1/-1 counter on another target creature.

Peat Bog

Peat Bog enters tapped with two depletion counters on it.
{T}, Remove a depletion counter from Peat Bog: Add {B}{B}. If there are no depletion counters on Peat Bog, sacrifice it.

Ur-Golem's Eye

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Souldrinker

Pay 3 life: Put a +1/+1 counter on Souldrinker.

Geode Golem

Trample
Whenever Geode Golem deals combat damage to a player, you may cast your commander from the command zone without paying its mana cost. (You still pay any additional costs.)

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Cinderhaze Wretch

{T}: Target player discards a card. Activate only during your turn.
Put a -1/-1 counter on Cinderhaze Wretch: Untap Cinderhaze Wretch.

Dross Golem

Affinity for Swamps (This spell costs {1} less to cast for each Swamp you control.)
Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Crystal Vein

{T}: Add {C}.
{T}, Sacrifice Crystal Vein: Add {C}{C}.

Nevinyrral's Disk

Nevinyrral's Disk enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Hollow One

This spell costs {2} less to cast for each card you've cycled or discarded this turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Deepwood Legate

If an opponent controls a Forest and you control a Swamp, you may cast this spell without paying its mana cost.
{B}: Deepwood Legate gets +1/+1 until end of turn.

Necrotic Ooze

As long as Necrotic Ooze is on the battlefield, it has all activated abilities of all creature cards in all graveyards.

Ebon Stronghold

Ebon Stronghold enters tapped.
{T}: Add {B}.
{T}, Sacrifice Ebon Stronghold: Add {B}{B}.

Cackling Imp

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.

Deadly Wanderings

As long as you control exactly one creature, that creature gets +2/+0 and has deathtouch and lifelink.

Lunar Avenger

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Remove a +1/+1 counter from Lunar Avenger: Lunar Avenger gains your choice of flying, first strike, or haste until end of turn.

Stonespeaker Crystal

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Stonespeaker Crystal: Exile any number of target players' graveyards. Draw a card.

Demonlord Belzenlok

Flying, trample
When Demonlord Belzenlok enters, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's mana value is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.

Sisay's Ring

Phantasmagorian

When you cast this spell, any player may discard three cards. If a player does, counter Phantasmagorian.
Discard three cards: Return Phantasmagorian from your graveyard to your hand.

Subterranean Hangar

Subterranean Hangar enters tapped.
{T}: Put a storage counter on Subterranean Hangar.
{T}, Remove any number of storage counters from Subterranean Hangar: Add {B} for each storage counter removed this way.

Mage-Ring Network

{T}: Add {C}.
{1}, {T}: Put a storage counter on Mage-Ring Network.
{T}, Remove any number of storage counters from Mage-Ring Network: Add {C} for each storage counter removed this way.