Giant Octopus

Giant Shark

Giant Shark can't attack unless defending player controls an Island.
Whenever Giant Shark blocks or becomes blocked by a creature that has been dealt damage this turn, Giant Shark gets +2/+0 and gains trample until end of turn.
When you control no Islands, sacrifice Giant Shark.

Razorclaw Bear

Whenever Razorclaw Bear becomes blocked, it gets +2/+2 until end of turn.

Leaping Lizard

{1}{G}: Leaping Lizard gets -0/-1 and gains flying until end of turn.

Thriving Ibex

When Thriving Ibex enters, you get {E}{E} (two energy counters).
Whenever Thriving Ibex attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it.

Brindle Shoat

When Brindle Shoat dies, create a 3/3 green Boar creature token.

Southern Elephant

Wild Elephant

Silverback Ape

Charging Badger

Balduvian Bears

Dawntreader Elk

{G}, Sacrifice Dawntreader Elk: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Arctic Foxes

Arctic Foxes can't be blocked by creatures with power 2 or greater as long as defending player controls a snow land.

Ferocious Pup

When Ferocious Pup enters, create a 2/2 green Wolf creature token.

Gargantuan Gorilla

At the beginning of your upkeep, you may sacrifice a Forest. If you sacrifice a snow Forest this way, Gargantuan Gorilla gains trample until end of turn. If you don't sacrifice a Forest, sacrifice Gargantuan Gorilla and it deals 7 damage to you.
{T}: Gargantuan Gorilla deals damage equal to its power to another target creature. That creature deals damage equal to its power to Gargantuan Gorilla.

Vexing Gull

Thieving Magpie

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Thieving Magpie deals damage to an opponent, draw a card.

Raging Gorilla

Whenever Raging Gorilla blocks or becomes blocked, it gets +2/-2 until end of turn.

Young Wolf

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.)

Killer Whale

{U}: Killer Whale gains flying until end of turn.

Guard Dogs

{2}{W}, {T}: Choose a permanent you control. Prevent all combat damage target creature would deal this turn if it shares a color with that permanent.

Camel

Banding (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)
As long as Camel is attacking, prevent all damage Deserts would deal to Camel and to creatures banded with Camel.

Horned Turtle

Canyon Wildcat

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)

Burglar Rat

When this creature enters, each opponent discards a card.

Giant Ox

Giant Ox crews Vehicles using its toughness rather than its power.

Whippoorwill

{G}{G}, {T}: Target creature can't be regenerated this turn. Damage that would be dealt to that creature this turn can't be prevented or dealt instead to another permanent or player. When the creature dies this turn, exile the creature.

Sea Eagle

Bay Falcon

Sanctuary Cat

Giant Albatross

Flying
When Giant Albatross dies, you may pay {1}{U}. If you do, for each creature that dealt damage to Giant Albatross this turn, destroy that creature unless its controller pays 2 life. A creature destroyed this way can't be regenerated.

Hammerhead Shark

Hammerhead Shark can't attack unless defending player controls an Island.

Pouncing Cheetah

Hungry Lynx

Cats you control have protection from Rats. (They can't be blocked, targeted, or dealt damage by Rats.)
At the beginning of your end step, target opponent creates a 1/1 black Rat creature token with deathtouch.
Whenever a Rat dies, put a +1/+1 counter on each Cat you control.

Grayscaled Gharial

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

Lynx

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)

Colorful Feiyi Sparrow

Flying (This creature can't be blocked except by creatures with flying or reach.)

Noxious Toad

When Noxious Toad dies, each opponent discards a card.

Wilson, Refined Grizzly

This spell can't be countered.
Vigilance, reach, trample
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Choose a Background (You can have a Background as a second commander.)

Savannah Lions

Durkwood Boars

Arctic Wolves

Cumulative upkeep {2} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When Arctic Wolves enters, draw a card.

Anaconda

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Wild Ox

Cave Tiger

Whenever Cave Tiger becomes blocked by a creature, Cave Tiger gets +1/+1 until end of turn.

Highland Game

When Highland Game dies, you gain 2 life.

Woolly Mammoths

Woolly Mammoths has trample as long as you control a snow land.

Horseshoe Crab

Dream Thrush

Flying
{T}: Target land becomes the basic land type of your choice until end of turn.

Bronzehide Lion

{G}{W}: Bronzehide Lion gains indestructible until end of turn.
When Bronzehide Lion dies, return it to the battlefield. It's an Aura enchantment with enchant creature you control and "{G}{W}: Enchanted creature gains indestructible until end of turn," and it loses all other abilities.

Leapfrog

Leapfrog has flying as long as you've cast an instant or sorcery spell this turn.

Colossal Whale

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Colossal Whale attacks, you may exile target creature defending player controls until Colossal Whale leaves the battlefield. (That creature returns under its owner's control.)

School of Piranha

At the beginning of your upkeep, sacrifice School of Piranha unless you pay {1}{U}.

Pack Rat

Pack Rat's power and toughness are each equal to the number of Rats you control.
{2}{B}, Discard a card: Create a token that's a copy of Pack Rat.

Golden Hind

Bear Cub

Hunting Cheetah

Whenever Hunting Cheetah deals damage to an opponent, you may search your library for a Forest card, reveal that card, put it into your hand, then shuffle.

Coveted Peacock

Flying
Whenever Coveted Peacock 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.)

Grizzly Bears

Pale Bears

Bellowing Elk

As long as you had another creature enter the battlefield under your control this turn, Bellowing Elk has trample and indestructible.

Wild Mammoth

At the beginning of your upkeep, if a player controls more creatures than each other player, the player who controls the most creatures gains control of Wild Mammoth.

Aggressive Mammoth

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Other creatures you control have trample.

Moss Viper

Golden Bear

Sewer Crocodile

{3}{U}: Sewer Crocodile can't be blocked this turn. This ability costs {3} less to activate if there are five or more mana values among cards in your graveyard.

Drainpipe Vermin

When Drainpipe Vermin dies, you may pay {B}. If you do, target player discards a card.

Howling Wolf

When Howling Wolf enters, you may search your library for up to three cards named Howling Wolf, reveal them, put them into your hand, then shuffle.

Great Whale

When Great Whale enters, untap up to seven lands.

Carrion Crow

Flying (This creature can't be blocked except by creatures with flying or reach.)
Carrion Crow enters tapped.

Mountain Goat

Snow Hound

{1}, {T}: Return Snow Hound and target green or blue creature you control to their owner's hand.

Black Cat

When Black Cat dies, target opponent discards a card at random.

Yoked Ox

Narwhal

Alpine Watchdog

Vigilance (Attacking doesn't cause this creature to tap.)

Alpine Grizzly

Skyshroud Condor

Cast this spell only if you've cast another spell this turn.
Flying

Dwarven Pony

{1}{R}, {T}: Target Dwarf creature gains mountainwalk until end of turn. (It can't be blocked as long as defending player controls a Mountain.)

Ashcoat Bear

Flash (You may cast this spell any time you could cast an instant.)

Manta Ray

Manta Ray can't attack unless defending player controls an Island.
Manta Ray can't be blocked except by blue creatures.
When you control no Islands, sacrifice Manta Ray.

Resolute Watchdog

Defender
{1}, Sacrifice Resolute Watchdog: Target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Ironhoof Ox

Ironhoof Ox can't be blocked by more than one creature.

Hooting Mandrills

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Trample

Forest Bear

Ambush Viper

Mesa Falcon

Flying
{1}{W}: Mesa Falcon gets +0/+1 until end of turn.

Man-o'-War

When Man-o'-War enters, return target creature to its owner's hand.

Bull Elephant

When Bull Elephant enters, sacrifice it unless you return two Forests you control to their owner's hand.

King Crab

{1}{U}, {T}: Put target green creature on top of its owner's library.

Coral Eel

Lone Wolf

You may have Lone Wolf assign its combat damage as though it weren't blocked.

Birds of Paradise

Jungle Lion

Screaming Seahawk

Flying
When Screaming Seahawk enters, you may search your library for a card named Screaming Seahawk, reveal it, put it into your hand, then shuffle.

Earth-Origin Yak

When Earth-Origin Yak enters, creatures you control get +1/+1 until end of turn.

Bloated Toad

Protection from blue
Cycling {2} ({2}, Discard this card: Draw a card.)

Pygmy Hippo

Whenever Pygmy Hippo attacks and isn't blocked, you may have defending player activate a mana ability of each land they control and lose all unspent mana. If you do, Pygmy Hippo assigns no combat damage this turn and at the beginning of your next main phase this turn, you add an amount of {C} equal to the amount of mana that player lost this way.