Emperor Crocodile

When you control no other creatures, sacrifice Emperor Crocodile.

Catacomb Crocodile

Hagra Crocodile

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

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.)

Vivien's Crocodile

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

Wardscale Crocodile

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

Phelddagrif

{G}: Phelddagrif gains trample until end of turn. Target opponent creates a 1/1 green Hippo creature token.
{W}: Phelddagrif gains flying until end of turn. Target opponent gains 2 life.
{U}: Return Phelddagrif to its owner's hand. Target opponent may draw a card.

Dross Crocodile

Crocodile of the Crossing

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

Marsh Crocodile

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

Lurking Crocodile

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

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.)

Veiled Crocodile

When a player has no cards in hand, if Veiled Crocodile is an enchantment, Veiled Crocodile becomes a 4/4 Crocodile creature.

Lapse of Certainty

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.