Call of the Herd

Create a 3/3 green Elephant creature token.
Flashback {3}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Chromatic Sphere

{1}, {T}, Sacrifice Chromatic Sphere: Add one mana of any color. Draw a card.

Krosan Beast

Threshold — Krosan Beast gets +7/+7 as long as seven or more cards are in your graveyard.

Brawn

Trample
As long as Brawn is in your graveyard and you control a Forest, creatures you control have trample.

Naturalize

Chromatic Star

{1}, {T}, Sacrifice Chromatic Star: Add one mana of any color.
When Chromatic Star is put into a graveyard from the battlefield, draw a card.

Forest

Sungrass Egg

{2}, {T}, Sacrifice Sungrass Egg: Add {G}{W}. Draw a card.

Plains

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. Brushland deals 1 damage to you.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Tranquil Thicket

Tranquil Thicket enters tapped.
{T}: Add {G}.
Cycling {G} ({G}, Discard this card: Draw a card.)

Nimble Mongoose

Shroud (This creature can't be the target of spells or abilities.)
Threshold — Nimble Mongoose gets +2/+2 as long as seven or more cards are in your graveyard.

Nantuko Monastery

{T}: Add {C}.
Threshold — {G}{W}: Nantuko Monastery becomes a 4/4 green and white Insect Monk creature with first strike until end of turn. It's still a land. Activate only if seven or more cards are in your graveyard.

Werebear

{T}: Add {G}.
Threshold — Werebear gets +3/+3 as long as seven or more cards are in your graveyard.

Mystic Enforcer

Protection from black
Threshold — As long as seven or more cards are in your graveyard, Mystic Enforcer gets +3/+3 and has flying.

Secluded Steppe

Secluded Steppe enters tapped.
{T}: Add {W}.
Cycling {W} ({W}, Discard this card: Draw a card.)

Anurid Brushhopper

Discard two cards: Exile Anurid Brushhopper. Return it to the battlefield under its owner's control at the beginning of the next end step.

Might of Oaks

Target creature gets +7/+7 until end of turn.

Centaur Garden

{T}: Add {G}. Centaur Garden deals 1 damage to you.
Threshold — {G}, {T}, Sacrifice Centaur Garden: Target creature gets +3/+3 until end of turn. Activate only if seven or more cards are in your graveyard.

Wild Mongrel

Discard a card: Wild Mongrel gets +1/+1 and becomes the color of your choice until end of turn.