Ethereal Elk

Trample
When Ethereal Elk enters, you may search your library and/or graveyard for a card named Vivien, Nature's Avenger, reveal it, and put it into your hand. If you search your library this way, shuffle.

Silverback Shaman

Trample
When Silverback Shaman dies, draw a card.

Season of Growth

Whenever a creature you control enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Whenever you cast a spell that targets a creature you control, draw a card.

Vivien, Nature's Avenger

+1: Put three +1/+1 counters on up to one target creature.
−1: Reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.
−6: Target creature gets +10/+10 and gains trample until end of turn.

Gnarlback Rhino

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever you cast a spell that targets Gnarlback Rhino, draw a card.

Titanic Growth

Target creature gets +4/+4 until end of turn.

Forest

Greenwood Sentinel

Vigilance (Attacking doesn't cause this creature to tap.)

Might of the Masses

Target creature gets +1/+1 until end of turn for each creature you control.

Barkhide Troll

Barkhide Troll enters with a +1/+1 counter on it.
{1}, Remove a +1/+1 counter from Barkhide Troll: Barkhide Troll gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Rabid Bite

Target creature you control deals damage equal to its power to target creature you don't control.

Wakeroot Elemental

{G}{G}{G}{G}{G}: Untap target land you control. It becomes a 5/5 Elemental creature with haste. It's still a land. (This effect lasts as long as that land remains on the battlefield.)

Growth Cycle

Target creature gets +3/+3 until end of turn. It gets an additional +2/+2 until end of turn for each card named Growth Cycle in your graveyard.

Aggressive Mammoth

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