Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Sundering Growth

Destroy target artifact or enchantment, then populate. (Create a token that's a copy of a creature token you control.)

Populate. Creatures you control gain indestructible until end of turn. (To populate, create a token that's a copy of a creature token you control.)

Vigilance, trample
Other Centaur creatures you control get +1/+1 and have vigilance and trample.

Create a 3/3 green Centaur creature token, then populate. (Create a token that's a copy of a creature token you control.)

At the beginning of your upkeep, populate. (Create a token that's a copy of a creature token you control.)

Populate X times. (To populate, create a token that's a copy of a creature token you control. Do this X times.)

{2}{G}: Exile target creature card from a graveyard, then populate. (Create a token that's a copy of a creature token you control.)

Create a token that's a copy of target creature you control.

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

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