Command the Dreadhorde

Choose any number of target creature and/or planeswalker cards in graveyards. Command the Dreadhorde deals damage to you equal to the total mana value of those cards. Put them onto the battlefield under your control.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter tapped.

Hunted Witness

When Hunted Witness dies, create a 1/1 white Soldier creature token with lifelink.

Anguished Unmaking

Exile target nonland permanent. You lose 3 life.

Tithe Taker

During your turn, spells your opponents cast cost {1} more to cast and abilities your opponents activate cost {1} more to activate unless they're mana abilities.
Afterlife 1 (When this creature dies, create a 1/1 white and black Spirit creature token with flying.)

The Elderspell

Destroy any number of target planeswalkers. Choose a planeswalker you control. Put two loyalty counters on it for each planeswalker destroyed this way.

Yahenni, Undying Partisan

Haste
Whenever a creature an opponent controls dies, put a +1/+1 counter on Yahenni, Undying Partisan.
Sacrifice another creature: Yahenni gains indestructible until end of turn.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Return to Dust

Exile target artifact or enchantment. If you cast this spell during your main phase, you may exile up to one other target artifact or enchantment.

Reveillark

Flying
When Reveillark leaves the battlefield, return up to two target creature cards with power 2 or less from your graveyard to the battlefield.
Evoke {5}{W} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Dreadhorde Invasion

At the beginning of your upkeep, you lose 1 life and amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)
Whenever a Zombie token you control with power 6 or greater attacks, it gains lifelink until end of turn.

Midnight Reaper

Whenever a nontoken creature you control dies, this creature deals 1 damage to you and you draw a card.

Bishop of Rebirth

Vigilance
Whenever Bishop of Rebirth attacks, you may return target creature card with mana value 3 or less from your graveyard to the battlefield.

Dawn

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Return all creature cards with power 2 or less from your graveyard to your hand.

Dusk

Destroy all creatures with power 3 or greater.

Dusk // Dawn

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on this creature.

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

God-Eternal Bontu

Menace
When God-Eternal Bontu enters, sacrifice any number of other permanents, then draw that many cards.
When God-Eternal Bontu dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Orzhov Enforcer

Deathtouch
Afterlife 1 (When this creature dies, create a 1/1 white and black Spirit creature token with flying.)

Orzhov Guildgate

This land enters tapped.
{T}: Add {W} or {B}.

Forsaken Sanctuary

Forsaken Sanctuary enters tapped.
{T}: Add {W} or {B}.

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Pawn of Ulamog

Whenever Pawn of Ulamog or another nontoken creature you control dies, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Plaguecrafter

When Plaguecrafter enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Orzhov Basilica

Orzhov Basilica enters tapped.
When Orzhov Basilica enters, return a land you control to its owner's hand.
{T}: Add {W}{B}.

Cruel Celebrant

Whenever Cruel Celebrant or another creature or planeswalker you control dies, each opponent loses 1 life and you gain 1 life.

Doomed Dissenter

When Doomed Dissenter dies, create a 2/2 black Zombie creature token.

Teysa Karlov

If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Creature tokens you control have vigilance and lifelink.

Gutterbones

Gutterbones enters tapped.
{1}{B}: Return Gutterbones from your graveyard to your hand. Activate only during your turn and only if an opponent lost life this turn.

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Mortify

Despark

Exile target permanent with mana value 4 or greater.

Adanto, the First Fort

(Transforms from Legion's Landing.)
{T}: Add {W}.
{2}{W}, {T}: Create a 1/1 white Vampire creature token with lifelink.

Legion's Landing

When Legion's Landing enters, create a 1/1 white Vampire creature token with lifelink.
When you attack with three or more creatures, transform Legion's Landing.

Legion's Landing // Adanto, the First Fort

Bojuka Bog

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

Swamp

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Sorin, Vengeful Bloodlord

During your turn, creatures and planeswalkers you control have lifelink.
+2: Sorin, Vengeful Bloodlord deals 1 damage to target player or planeswalker.
−X: Return target creature card with mana value X from your graveyard to the battlefield. That creature is a Vampire in addition to its other types.

Doomed Traveler

When Doomed Traveler dies, create a 1/1 white Spirit creature token with flying.

Butcher of Malakir

Flying
Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature of their choice.

Plains

Fumigate

Destroy all creatures. You gain 1 life for each creature destroyed this way.

Elenda, the Dusk Rose

Lifelink
Whenever another creature dies, put a +1/+1 counter on Elenda, the Dusk Rose.
When Elenda dies, create X 1/1 white Vampire creature tokens with lifelink, where X is Elenda's power.