Christopher Burdett

Don't try to ride this steed unless you've got gills too.

Breaching Hippocamp

Flash (You may cast this spell any time you could cast an instant.)\r
When Breaching Hippocamp enters the battlefield, untap another target creature you control.

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, untap another target creature you control.

Rikala, Homarid King

At the beginning of your upkeep, put a tide counter on Rikala. Then if there are four or more tide counters on Rikala, remove them.
Creatures you control get +1/+0 for each tide counter on Rikala.
Whenever you tap an Island for mana, if there are three or more tide counters on Rikala, add an additional {U}.

Stinging Lionfish

Whenever you cast your first spell during each opponent's turn, you may tap or untap target nonland permanent.

The swarm leaves behind a flawless pattern that only occasionally threatens the structural integrity of the wood.

Fretwork Colony

This creature can't block.
At the beginning of your upkeep, put a +1/+1 counter on this creature and you lose 1 life.

Cephalid Inkmage

When this creature enters, surveil 3. (Look at the top three cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Threshold — This creature can't be blocked as long as there are seven or more cards in your graveyard.

Cackling Prowler

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Morbid — At the beginning of your end step, if a creature died this turn, put a +1/+1 counter on this creature.

Coveted Peacock

Flying
Whenever this creature attacks, you may goad target creature defending player controls. (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Lying to a fish is such an unthinkable act, most planets don't even have a law against it.

Blufferfish

{3}{U}: An opponent tells you a statement about themselves and secretly notes whether it's true or false. You guess which it is. If you guessed correctly, this creature gets +2/+0 and can't be blocked this turn.

Monstrous War-Leech

Kicker {U} (You may pay an additional {U} as you cast this spell.)
As this creature enters, if it was kicked, mill four cards. (To mill a card, put the top card of your library into your graveyard.)
Monstrous War-Leech's power and toughness are each equal to the greatest mana value among cards in your graveyard.

In New Capenna, it's survival of the richest.

Bribe Taker

Trample
When this creature enters, for each kind of counter on permanents you control, you may put your choice of a +1/+1 counter or a counter of that kind on this creature.

Shifting Shadow

Enchant creature
Enchanted creature has haste and "At the beginning of your upkeep, destroy this creature. Reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield and attach Shifting Shadow to it, then put all other cards revealed this way on the bottom of your library in a random order."

If an elf can dream it, a dwarf can build it, and a gremlin can eat it.

Salivating Gremlins

Whenever an artifact you control enters, this creature gets +2/+0 and gains trample until end of turn.

It swims upon the winds and soars through the waves.

Shimmerwing Chimera

Flying
At the beginning of your upkeep, return up to one other target enchantment you control to its owner's hand.

Where its feet tread, the thunder of many others will follow.

Nylea's Forerunner

Trample
Other creatures you control have trample.

Portent

Look at the top three cards of target player's library, then put them back in any order. You may have that player shuffle.
Draw a card at the beginning of the next turn's upkeep.

As its parched flesh withers away, its malignant hunger grows.

Festering Mummy

When this creature dies, you may put a -1/-1 counter on target creature.

Travelers to Lathnu, high on the Devra Cliffs, need not fear the political strife of Ghirapur . . . but they have other dangers to worry about.

Lathnu Sailback

Some say tales of the Narnam greenhouse are told to scare the children, but every tale grows from a seed of truth.

Narnam Cobra

{G}: This creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Hunger makes a leucrocota dangerous. A full belly makes it angry and dangerous.

Ravenous Leucrocota

Vigilance
{6}{G}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)

Gudul Lurker

This creature can't be blocked.
Megamorph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)

"Why eat now what could one day grow into a feast?"
—Ojutai, translated from Draconic

Ancient Carp

Loathsome Catoblepas

{2}{G}: This creature must be blocked this turn if able.
When this creature dies, target creature an opponent controls gets -3/-3 until end of turn.