Thunderfoot Baloth

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

Sol Ring

Garruk's Horde

Trample
Play with the top card of your library revealed.
You may cast creature spells from the top of your library. (Do this only any time you could cast that creature spell. You still pay the spell's costs.)

Goreclaw, Terror of Qal Sisma

Creature spells you cast with power 4 or greater cost {2} less to cast.
Whenever Goreclaw, Terror of Qal Sisma attacks, each creature you control with power 4 or greater gets +1/+1 and gains trample until end of turn.

Garruk's Packleader

Whenever another creature you control with power 3 or greater enters, you may draw a card.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Hulking Raptor

Ward {2}
At the beginning of your first main phase, add {G}{G}.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample

Aggressive Mammoth

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

Surrak, the Hunt Caller

Formidable — At the beginning of combat on your turn, if creatures you control have total power 8 or greater, target creature you control gains haste until end of turn.

Bear Down

Destroy target artifact or enchantment. (Then exile this card. You may cast the creature later from exile.)