Guul Draz Mucklord

When Guul Draz Mucklord dies, put a +1/+1 counter on target creature you control.

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters the battlefield, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.

Catacomb Crocodile

Kheru Dreadmaw

Defender
{1}{G}, Sacrifice another creature: You gain life equal to the sacrificed creature's toughness.

Crocanura

Reach (This creature can block creatures with flying.)
Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Sol Ring

Scuttlegator

Defender
{6}{G/U}{G/U}: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)
As long as Scuttlegator has a +1/+1 counter on it, it can attack as though it didn't have defender.

Vivien's Crocodile

Vivien's Crocodile gets +1/+1 as long as you control a Vivien planeswalker.

Crocodile of the Crossing

Haste
When Crocodile of the Crossing enters the battlefield, put a -1/-1 counter on target creature you control.

Scaled Behemoth

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Wardscale Crocodile

Arcane Signet

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

Ammit Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
Whenever an opponent casts a spell, put a -1/-1 counter on Ammit Eternal.
Whenever Ammit Eternal deals combat damage to a player, remove all -1/-1 counters from it.

Hagra Crocodile

Hagra Crocodile can't block.
Landfall — Whenever a land enters the battlefield under your control, Hagra Crocodile gets +2/+2 until end of turn.

Tenacious Hunter

As long as a creature has a -1/-1 counter on it, Tenacious Hunter has vigilance and deathtouch.

Algae Gharial

Shroud (This creature can't be the target of spells or abilities.)
Whenever another creature dies, you may put a +1/+1 counter on Algae Gharial.

Lurking Crocodile

Bloodthirst 1 (If an opponent was dealt damage this turn, this creature enters the battlefield with a +1/+1 counter on it.)
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Marsh Crocodile

When Marsh Crocodile enters the battlefield, return a blue or black creature you control to its owner's hand.
When Marsh Crocodile enters the battlefield, each player discards a card.

Moldering Karok

Baleful Ammit

Lifelink
When Baleful Ammit enters the battlefield, put a -1/-1 counter on target creature you control.

Grayscaled Gharial

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)

Skeletal Crocodile

Spined Karok

Dukhara Scavenger

When Dukhara Scavenger enters the battlefield, you may put target artifact or creature card from your graveyard on top of your library.

Dross Crocodile

Emperor Crocodile

When you control no other creatures, sacrifice Emperor Crocodile.

Sandbar Crocodile

Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)

Stonefare Crocodile

{2}{B}: Stonefare Crocodile gains lifelink until end of turn. (Damage dealt by this creature also causes you to gain that much life.)