Colossification

Enchant creature
When Colossification enters, tap enchanted creature.
Enchanted creature gets +20/+20.

Aggressive Mammoth

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

Arbor Elf

Colossus of Akros

Defender, indestructible
{10}: Monstrosity 10. (If this creature isn't monstrous, put ten +1/+1 counters on it and it becomes monstrous.)
As long as Colossus of Akros is monstrous, it has trample and can attack as though it didn't have defender.

Arasta of the Endless Web

Reach
Whenever an opponent casts an instant or sorcery spell, create a 1/2 green Spider creature token with reach.

Bounty of Might

Target creature gets +3/+3 until end of turn.
Target creature gets +3/+3 until end of turn.
Target creature gets +3/+3 until end of turn.

Champion of Rhonas

You may exert Champion of Rhonas as it attacks. When you do, you may put a creature card from your hand onto the battlefield. (An exerted creature won't untap during your next untap step.)

Beastcaller Savant

Haste
{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Chancellor of the Tangle

You may reveal this card from your opening hand. If you do, at the beginning of your first main phase of the game, add {G}.
Vigilance, reach

Battle Mammoth

Trample
Whenever a permanent you control becomes the target of a spell or ability an opponent controls, you may draw a card.
Foretell {2}{G}{G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Cloudthresher

Flash
Reach
When Cloudthresher enters, it deals 2 damage to each creature with flying and each player.
Evoke {2}{G}{G} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)