Spitting Slug

Whenever Spitting Slug blocks or becomes blocked, you may pay {1}{G}. If you do, Spitting Slug gains first strike until end of turn. Otherwise, each creature blocking or blocked by Spitting Slug gains first strike until end of turn.

Congregation Gryff

Flying, lifelink
Whenever Congregation Gryff attacks while saddled, it gets +X/+X until end of turn, where X is the number of Mounts you control.
Saddle 3 (Tap any number of other creatures you control with total power 3 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Thalakos Scout

Shadow (This creature can block or be blocked by only creatures with shadow.)
Discard a card: Return Thalakos Scout to its owner's hand.

Dawn Gryff

Thalakos Seer

Shadow (This creature can block or be blocked by only creatures with shadow.)
When Thalakos Seer leaves the battlefield, draw a card.

Thalakos Sentry

Shadow (This creature can block or be blocked by only creatures with shadow.)

Standard Bearer

While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least one Flagbearer on the battlefield if able.

Surrakar Banisher

When Surrakar Banisher enters, you may return target tapped creature to its owner's hand.

Hushwing Gryff

Flash
Flying
Creatures entering don't cause abilities to trigger.

Sinister Starfish

{T}: Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Bubbling Beebles

Bubbling Beebles can't be blocked as long as defending player controls an enchantment.

Have

Slith Predator

Trample
Whenever Slith Predator deals combat damage to a player, put a +1/+1 counter on it.

Waildrifter

Flying
If Waildrifter would be put into a graveyard from anywhere, exile it instead.

Galedrifter

Flying
Disturb {4}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Galedrifter // Waildrifter

Tyr's Blessing

Target creature gains indestructible until end of turn. (Then exile this card. You may cast the creature later from exile.)

Blessed Hippogriff

Flying
Whenever Blessed Hippogriff attacks, target attacking creature without flying gains flying until end of turn.

Blessed Hippogriff // Tyr's Blessing

Surrakar Marauder

Landfall — Whenever a land you control enters, Surrakar Marauder gains intimidate until end of turn. (It can't be blocked except by artifact creatures and/or creatures that share a color with it.)

Surrakar Spellblade

Whenever you cast an instant or sorcery spell, you may put a charge counter on Surrakar Spellblade.
Whenever Surrakar Spellblade deals combat damage to a player, you may draw X cards, where X is the number of charge counters on it.

Reckless Pangolin

Whenever Reckless Pangolin attacks, it gets +1/+1 until end of turn.

Thalakos Drifters

Discard a card: Thalakos Drifters gains shadow until end of turn. (It can block or be blocked by only creatures with shadow.)

Gloom Pangolin

Oneirophage

Flying
Whenever you draw a card, put a +1/+1 counter on Oneirophage.

Gluttonous Slug

Menace
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Wretched Gryff

Emerge {5}{U} (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, draw a card.
Flying

Thalakos Mistfolk

Shadow (This creature can block or be blocked by only creatures with shadow.)
{U}: Put Thalakos Mistfolk on top of its owner's library.

Hexgold Slith

When Hexgold Slith enters, you get {E}{E} (two energy counters).
Whenever Hexgold Slith attacks, you may pay {E}{E}. If you do, it gains first strike until end of turn.
Whenever Hexgold Slith deals combat damage to a player, put a +1/+1 counter on it.

Cephalopod Sentry

Flying
Cephalopod Sentry's power is equal to the number of artifacts you control.

Thalakos Dreamsower

Shadow (This creature can block or be blocked by only creatures with shadow.)
You may choose not to untap Thalakos Dreamsower during your untap step.
Whenever Thalakos Dreamsower deals damage to an opponent, tap target creature. That creature doesn't untap during its controller's untap step for as long as Thalakos Dreamsower remains tapped.

Noggle Ransacker

When Noggle Ransacker enters, each player draws two cards, then discards a card at random.

Thermopod

{S}: Thermopod gains haste until end of turn. ({S} can be paid with one mana from a snow source.)
Sacrifice a creature: Add {R}.

Molder Slug

At the beginning of each player's upkeep, that player sacrifices an artifact of their choice.

Slith Strider

Whenever Slith Strider becomes blocked, draw a card.
Whenever Slith Strider deals combat damage to a player, put a +1/+1 counter on it.

Slith Bloodletter

Whenever Slith Bloodletter deals combat damage to a player, put a +1/+1 counter on it.
{1}{B}: Regenerate Slith Bloodletter.

Prowling Pangolin

When Prowling Pangolin enters, any player may sacrifice two creatures of their choice. If a player does, sacrifice Prowling Pangolin.

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.

Skyclave Squid

Defender
Landfall — Whenever a land you control enters, Skyclave Squid can attack this turn as though it didn't have defender.

Thought Sponge

Flash
Thought Sponge enters with a number of +1/+1 counters on it equal to the greatest number of cards an opponent has drawn this turn.
When Thought Sponge dies, draw cards equal to its power.

Ridgescale Tusker

When Ridgescale Tusker enters, put a +1/+1 counter on each other creature you control.

Anavolver

Kicker {1}{U} and/or {B} (You may pay an additional {1}{U} and/or {B} as you cast this spell.)
If Anavolver was kicked with its {1}{U} kicker, it enters with two +1/+1 counters on it and with flying.
If Anavolver was kicked with its {B} kicker, it enters with a +1/+1 counter on it and with "Pay 3 life: Regenerate Anavolver."

Soul-Guide Gryff

Flying
When Soul-Guide Gryff enters, exile up to one target card from a graveyard.

Noggle Bandit

Noggle Bandit can't be blocked except by creatures with defender.

Bouncing Beebles

Bouncing Beebles can't be blocked as long as defending player controls an artifact.

Shore Keeper

{7}{U}, {T}, Sacrifice Shore Keeper: Draw three cards.

Morkrut Necropod

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Morkrut Necropod attacks or blocks, sacrifice another creature or land.

Slith Ascendant

Flying
Whenever Slith Ascendant deals combat damage to a player, put a +1/+1 counter on it.

Catacomb Slug

Cryptic Trilobite

Cryptic Trilobite enters with X +1/+1 counters on it.
Remove a +1/+1 counter from Cryptic Trilobite: Add {C}{C}. Spend this mana only to activate abilities.
{1}, {T}: Put a +1/+1 counter on Cryptic Trilobite.

Cetavolver

Kicker {1}{R} and/or {G} (You may pay an additional {1}{R} and/or {G} as you cast this spell.)
If Cetavolver was kicked with its {1}{R} kicker, it enters with two +1/+1 counters on it and with first strike.
If Cetavolver was kicked with its {G} kicker, it enters with a +1/+1 counter on it and with trample.

Rakavolver

Kicker {1}{W} and/or {U} (You may pay an additional {1}{W} and/or {U} as you cast this spell.)
If Rakavolver was kicked with its {1}{W} kicker, it enters with two +1/+1 counters on it and with "Whenever Rakavolver deals damage, you gain that much life."
If Rakavolver was kicked with its {U} kicker, it enters with a +1/+1 counter on it and with flying.

Fylamarid

Flying
Fylamarid can't be blocked by blue creatures.
{U}: Target creature becomes blue until end of turn.

Walking Sponge

{T}: Target creature loses your choice of flying, first strike, or trample until end of turn.

Drownyard Lurker

Vigilance
When you cast or cycle Drownyard Lurker, create a 0/1 colorless Eldrazi Spawn creature token with "Sacrifice this creature: Add {C}."
Cycling {2}{U} ({2}{U}, Discard this card: Draw a card.)

Sand Squid

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
You may choose not to untap Sand Squid during your untap step.
{T}: Tap target creature. That creature doesn't untap during its controller's untap step for as long as Sand Squid remains tapped.

Spiny Starfish

{U}: Regenerate Spiny Starfish.
At the beginning of each end step, if Spiny Starfish regenerated this turn, create a 0/1 blue Starfish creature token for each time it regenerated this turn.

Necravolver

Kicker {1}{G} and/or {W} (You may pay an additional {1}{G} and/or {W} as you cast this spell.)
If Necravolver was kicked with its {1}{G} kicker, it enters with two +1/+1 counters on it and with trample.
If Necravolver was kicked with its {W} kicker, it enters with a +1/+1 counter on it and with "Whenever Necravolver deals damage, you gain that much life."

Degavolver

Kicker {1}{B} and/or {R} (You may pay an additional {1}{B} and/or {R} as you cast this spell.)
If Degavolver was kicked with its {1}{B} kicker, it enters with two +1/+1 counters on it and with "Pay 3 life: Regenerate Degavolver."
If Degavolver was kicked with its {R} kicker, it enters with a +1/+1 counter on it and with first strike.

Giant Slug

{5}: At the beginning of your next upkeep, choose a basic land type. Giant Slug gains landwalk of the chosen type until the end of that turn. (It can't be blocked as long as defending player controls a land of that type.)

Thalakos Deceiver

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever Thalakos Deceiver attacks and isn't blocked, you may sacrifice it. If you do, gain control of target creature. (This effect lasts indefinitely.)

Gulf Squid

When Gulf Squid enters, tap all lands target player controls.

Loyal Gryff

Flash
Flying
When Loyal Gryff enters, you may return another creature you control to its owner's hand.

Slith Firewalker

Haste
Whenever Slith Firewalker deals combat damage to a player, put a +1/+1 counter on it.

Shoreline Salvager

Whenever Shoreline Salvager deals combat damage to a player, if you control an Island, you may draw a card.

Arcbound Slith

Whenever Arcbound Slith deals combat damage to a player, put a +1/+1 counter on it.
Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Razor Hippogriff

Flying
When Razor Hippogriff enters, return target artifact card from your graveyard to your hand. You gain life equal to that card's mana value.

Bronze Sable

Scuttling Sliver

Sliver creatures you control have "{2}: Untap this creature."

Noggle Bridgebreaker

When Noggle Bridgebreaker enters, return a land you control to its owner's hand.

Noggle Hedge-Mage

When Noggle Hedge-Mage enters, if you control two or more Islands, you may tap two target permanents.
When Noggle Hedge-Mage enters, if you control two or more Mountains, you may have Noggle Hedge-Mage deal 2 damage to target player or planeswalker.

Elder Spawn

At the beginning of your upkeep, unless you sacrifice an Island, sacrifice Elder Spawn and it deals 6 damage to you.
Elder Spawn can't be blocked by red creatures.

Etched Slith

Menace
Whenever Etched Slith deals combat damage to a player, put a +1/+1 counter on it. When you do, you may remove a counter from another target permanent or opponent.

Sigiled Starfish

{T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Coalition Honor Guard

Electryte

Whenever Electryte deals combat damage to defending player, it deals damage equal to its power to each blocking creature.