It of the Horrid Swarm

Emerge {6}{G} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When you cast this spell, create two 1/1 green Insect creature tokens.

Black Market

Whenever a creature dies, put a charge counter on Black Market.
At the beginning of your first main phase, add {B} for each charge counter on Black Market.

Grim Backwoods

{T}: Add {C}.
{2}{B}{G}, {T}, Sacrifice a creature: Draw a card.

Bane of the Living

Morph {X}{B}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Bane of the Living is turned face up, all creatures get -X/-X until end of turn.

Evolutionary Leap

{G}, Sacrifice a creature: Reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.

Memorial to Folly

Memorial to Folly enters tapped.
{T}: Add {B}.
{2}{B}, {T}, Sacrifice Memorial to Folly: Return target creature card from your graveyard to your hand.

Moldervine Reclamation

Whenever a creature you control dies, you gain 1 life and draw a card.

Vorapede

Vigilance, trample
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Jund Panorama

{T}: Add {C}.
{1}, {T}, Sacrifice Jund Panorama: Search your library for a basic Swamp, Mountain, or Forest card, put it onto the battlefield tapped, then shuffle.

Traveler's Amulet

{1}, Sacrifice Traveler's Amulet: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Vulturous Zombie

Flying
Whenever a card is put into an opponent's graveyard from anywhere, put a +1/+1 counter on Vulturous Zombie.

Phyrexian Vault

{2}, {T}, Sacrifice a creature: Draw a card.

Getting

Eldrazi Monument

Creatures you control get +1/+1 and have flying and indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Skylasher

Flash
This spell can't be countered.
Reach, protection from blue

Junkyo Bell

At the beginning of your upkeep, you may have target creature you control get +X/+X until end of turn, where X is the number of creatures you control. If you do, sacrifice that creature at the beginning of the next end step.

Attrition

{B}, Sacrifice a creature: Destroy target nonblack creature.

Necropede

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When Necropede dies, you may put a -1/-1 counter on target creature.

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.

Door of Destinies

As Door of Destinies enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Grafted Exoskeleton

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever Grafted Exoskeleton becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Nantuko Shade

{B}: Nantuko Shade gets +1/+1 until end of turn.

Crash of Rhino Beetles

Trample
Crash of Rhino Beetles gets +10/+10 as long as you control ten or more lands.

Altar's Reap

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Beastmaster Ascension

Whenever a creature you control attacks, you may put a quest counter on Beastmaster Ascension.
As long as Beastmaster Ascension has seven or more quest counters on it, creatures you control get +5/+5.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice Field of Ruin: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Golgari Keyrune

{T}: Add {B} or {G}.
{B}{G}: Golgari Keyrune becomes a 2/2 black and green Insect artifact creature with deathtouch until end of turn.

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Blightbeetle

Protection from green (This creature can't be blocked, targeted, dealt damage, enchanted, or equipped by anything green.)
Creatures your opponents control can't have +1/+1 counters put on them.

Unyaro Bees

Flying
{G}: Unyaro Bees gets +1/+1 until end of turn.
{3}{G}, Sacrifice Unyaro Bees: It deals 2 damage to any target.

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Command Tower

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

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Tainted Wood

{T}: Add {C}.
{T}: Add {B} or {G}. Activate only if you control a Swamp.

Invasive Species

When Invasive Species enters, return another permanent you control to its owner's hand.

Hornet Queen

Flying, deathtouch
When Hornet Queen enters, create four 1/1 green Insect creature tokens with flying and deathtouch.

Ant Queen

{1}{G}: Create a 1/1 green Insect creature token.

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Ashnod's Altar

Bond Beetle

When Bond Beetle enters, put a +1/+1 counter on target creature.

Arcane Signet

Crop Rotation

As an additional cost to cast this spell, sacrifice a land.
Search your library for a land card, put that card onto the battlefield, then shuffle.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

Spawning Pit

Sacrifice a creature: Put a charge counter on Spawning Pit.
{1}, Remove two charge counters from Spawning Pit: Create a 2/2 colorless Spawn artifact creature token.

Bankrupt in Blood

As an additional cost to cast this spell, sacrifice two creatures.
Draw three cards.

Skull Storm

When you cast this spell, copy it for each time you've cast your commander from the command zone this game.
Each opponent sacrifices a creature. Each opponent who can't loses half their life, rounded up.

The Gitrog Monster

Deathtouch
At the beginning of your upkeep, sacrifice The Gitrog Monster unless you sacrifice a land.
You may play an additional land on each of your turns.
Whenever one or more land cards are put into your graveyard from anywhere, draw a card.

Nest of Scarabs

Whenever you put one or more -1/-1 counters on a creature, create that many 1/1 black Insect creature tokens.

Phyrexian Tower

{T}: Add {C}.
{T}, Sacrifice a creature: Add {B}{B}.

Zanikev Locust

Flying
Scavenge {2}{B}{B} ({2}{B}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Xantid Swarm

Flying
Whenever Xantid Swarm attacks, defending player can't cast spells this turn.

Living Hive

Trample
Whenever Living Hive deals combat damage to a player, create that many 1/1 green Insect creature tokens.

Mire in Misery

Each opponent sacrifices a creature or enchantment.

Carrion Ants

{1}: Carrion Ants gets +1/+1 until end of turn.

Swamp Mosquito

Flying
Whenever Swamp Mosquito attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)

Grave-Shell Scarab

{1}, Sacrifice Grave-Shell Scarab: Draw a card.
Dredge 1 (If you would draw a card, you may mill a card instead. If you do, return this card from your graveyard to your hand.)

Foundry Hornet

Flying
When Foundry Hornet enters, if you control a creature with a +1/+1 counter on it, creatures your opponents control get -1/-1 until end of turn.

Scute Mob

At the beginning of your upkeep, if you control five or more lands, put four +1/+1 counters on Scute Mob.

Deadbridge Goliath

Scavenge {4}{G}{G} ({4}{G}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Sakura-Tribe Elder

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Yavimaya Hollow

{T}: Add {C}.
{G}, {T}: Regenerate target creature.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Roiling Regrowth

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Endless Cockroaches

When Endless Cockroaches dies, return it to its owner's hand.

Rust Scarab

Whenever Rust Scarab becomes blocked, you may destroy target artifact or enchantment defending player controls.

Nessian Hornbeetle

At the beginning of combat on your turn, if you control another creature with power 4 or greater, put a +1/+1 counter on Nessian Hornbeetle.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Grave Pact

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

Momentous Fall

As an additional cost to cast this spell, sacrifice a creature.
You draw cards equal to the sacrificed creature's power, then you gain life equal to its toughness.

Deathsprout

Destroy target creature. Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Meren of Clan Nel Toth

Whenever another creature you control dies, you get an experience counter.
At the beginning of your end step, choose target creature card in your graveyard. If that card's mana value is less than or equal to the number of experience counters you have, return it to the battlefield. Otherwise, put it into your hand.

Sol Ring

Iridescent Hornbeetle

At the beginning of your end step, create a 1/1 green Insect creature token for each +1/+1 counter you've put on creatures under your control this turn.

Carrion

As an additional cost to cast this spell, sacrifice a creature.
Create X 0/1 black Insect creature tokens, where X is the sacrificed creature's power.

Corpsejack Menace

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on it instead.

Broodhatch Nantuko

Whenever Broodhatch Nantuko is dealt damage, you may create that many 1/1 green Insect creature tokens.
Morph {2}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Parallel Lives

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Kindred Summons

Choose a creature type. Reveal cards from the top of your library until you reveal X creature cards of the chosen type, where X is the number of creatures you control of that type. Put those cards onto the battlefield, then shuffle the rest of the revealed cards into your library.

Mazirek, Kraul Death Priest

Flying
Whenever a player sacrifices another permanent, put a +1/+1 counter on each creature you control.

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.

Wave of Vitriol

Each player sacrifices all artifacts, enchantments, and nonbasic lands they control. For each land sacrificed this way, its controller may search their library for a basic land card and put it onto the battlefield tapped. Then each player who searched their library this way shuffles.

It That Betrays

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)
Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control.

Kraul Harpooner

Reach
Undergrowth — When Kraul Harpooner enters, choose up to one target creature you don't control with flying. Kraul Harpooner gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard, then you may have Kraul Harpooner fight that creature.

Brood of Cockroaches

When Brood of Cockroaches is put into your graveyard from the battlefield, at the beginning of the next end step, you lose 1 life and return Brood of Cockroaches to your hand.

Giant Adephage

Trample
Whenever Giant Adephage deals combat damage to a player, create a token that's a copy of Giant Adephage.

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.

Ironshell Beetle

When Ironshell Beetle enters, put a +1/+1 counter on target creature.

Carnage Altar

Swarm Shambler

Swarm Shambler enters with a +1/+1 counter on it.
Whenever a creature you control with a +1/+1 counter on it becomes the target of a spell an opponent controls, create a 1/1 green Insect creature token.
{1}, {T}: Put a +1/+1 counter on Swarm Shambler.

Triumph of the Hordes

Until end of turn, creatures you control get +1/+1 and gain trample and infect. (Creatures with infect deal damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Fleshbag Marauder

When Fleshbag Marauder enters, each player sacrifices a creature.

Swamp

Swarmyard

{T}: Add {C}.
{T}: Regenerate target Insect, Rat, Spider, or Squirrel. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

Crawling Sensation

At the beginning of your upkeep, you may mill two cards. (You may put the top two cards of your library into your graveyard.)
Whenever one or more land cards are put into your graveyard from anywhere for the first time each turn, create a 1/1 green Insect creature token.

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Moldgraf Monstrosity

Trample
When Moldgraf Monstrosity dies, exile it, then return two creature cards at random from your graveyard to the battlefield.

Pillar of Origins

As Pillar of Origins enters, choose a creature type.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Priest of Forgotten Gods

{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature. You add {B}{B} and draw a card.

Barter in Blood

Hex Parasite

{X}{B/P}: Remove up to X counters from target permanent. For each counter removed this way, Hex Parasite gets +1/+0 until end of turn. ({B/P} can be paid with either {B} or 2 life.)