Nettle Sentinel

Nettle Sentinel doesn't untap during your untap step.
Whenever you cast a green spell, you may untap Nettle Sentinel.

Scythe Tiger

Shroud (This creature can't be the target of spells or abilities.)
When Scythe Tiger enters, sacrifice it unless you sacrifice a land.

Young Wolf

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Bayou Groff

As an additional cost to cast this spell, sacrifice a creature or pay {3}.

Forest

Winding Way

Choose creature or land. Reveal the top four cards of your library. Put all cards of the chosen type revealed this way into your hand and the rest into your graveyard.

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

Garruk's Companion

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Quirion Ranger

Return a Forest you control to its owner's hand: Untap target creature. Activate only once each turn.

Rogue Elephant

When Rogue Elephant enters, sacrifice it unless you sacrifice a Forest.

Experiment One

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Remove two +1/+1 counters from Experiment One: Regenerate Experiment One. (The next time this creature would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)