Impervious Greatwurm

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Indestructible

Terrian, World Tyrant

Worldspine Wurm

Trample
When this creature dies, create three 5/5 green Wurm creature tokens with trample.
When Worldspine Wurm is put into a graveyard from anywhere, shuffle it into its owner's library.

Aggressive Mammoth

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

Plated Slagwurm

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

Hydra Omnivore

Whenever this creature deals combat damage to an opponent, it deals that much damage to each other opponent.

Ghoultree

This spell costs {1} less to cast for each creature card in your graveyard.

Ancient Brontodon

Panglacial Wurm

Trample
While you're searching your library, you may cast this card from your library.

Hunted Troll

When this creature enters, target opponent creates four 1/1 blue Faerie creature tokens with flying.
{G}: Regenerate this creature.

Ghalta, Stampede Tyrant

Trample
When Ghalta enters, put any number of creature cards from your hand onto the battlefield.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Caller of the Pack

Trample
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Ghalta and Mavren

Trample
Whenever you attack, choose one —
• Create a tapped and attacking X/X green Dinosaur creature token with trample, where X is the greatest power among other attacking creatures.
• Create X 1/1 white Vampire creature tokens with lifelink, where X is the number of other attacking creatures.