Rampaging Rendhorn

Riot (This creature enters with your choice of a +1/+1 counter or haste.)

Bedhead Beastie

Menace (This creature can't be blocked except by two or more creatures.)
Mountaincycling {2} ({2}, Discard this card: Search your library for a Mountain card, reveal it, put it into your hand, then shuffle.)

Sagu Pummeler

Reach
Renew — {4}{G}, Exile this card from your graveyard: Put two +1/+1 counters and a reach counter on target creature. Activate only as a sorcery.

Coliseum Behemoth

Trample
When this creature enters, choose one —
• Destroy target artifact or enchantment.
• Draw a card.

Thunderfoot Baloth

Trample
Lieutenant — As long as you control your commander, this creature gets +2/+2 and other creatures you control get +2/+2 and have trample.

Spined Tyrranax

At the beginning of combat on your turn, you may pay {2}{G}. When you do, put a +1/+1 counter on target creature. That creature gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Kona, Rescue Beastie

Survival — At the beginning of your second main phase, if Kona is tapped, you may put a permanent card from your hand onto the battlefield.

Cultivator Colossus

Trample
Cultivator Colossus's power and toughness are each equal to the number of lands you control.
When this creature enters, you may put a land card from your hand onto the battlefield tapped. If you do, draw a card and repeat this process.

Rampaging Baloths

Trample
Landfall — Whenever a land you control enters, create a 4/4 green Beast creature token.

Slinza, the Spiked Stampede

Beast spells you cast cost {2} less to cast.
Each other Beast creature you control enters with an additional +1/+1 counter on it.
Whenever Slinza or another creature with power 4 or greater enters, you may pay {1}{R/G}. When you do, Slinza fights target creature you don't control.

Red XIII, Proud Warrior

Vigilance, trample
Other modified creatures you control have vigilance and trample. (Equipment, Auras you control, and counters are modifications.)
Cosmo Memory — When Red XIII enters, return target Aura or Equipment card from your graveyard to your hand.

Protean Hulk

When this creature dies, search your library for any number of creature cards with total mana value 6 or less, put them onto the battlefield, then shuffle.

Plated Kilnbeast

Menace (This creature can't be blocked except by two or more creatures.)

Bonded Herdbeast

{4}{R/P}: Transform this creature. Activate only as a sorcery. ({R/P} can be paid with either {R} or 2 life.)

Bonded Herdbeast // Plated Kilnbeast

Giant Cindermaw

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Players can't gain life.

Quartzwood Crasher

Trample
Whenever one or more creatures you control with trample deal combat damage to a player, create an X/X green Dinosaur Beast creature token with trample, where X is the amount of damage those creatures dealt to that player.

Affectionate Indrik

When this creature enters, you may have it fight target creature you don't control. (Each deals damage equal to its power to the other.)