Mild-Mannered Librarian

{3}{G}: This creature becomes a Werewolf. Put two +1/+1 counters on it and you draw a card. Activate only once.

Wolfkin Bond

Enchant creature
When Wolfkin Bond enters, create a 2/2 green Wolf creature token.
Enchanted creature gets +2/+2.

Arlinn, Voice of the Pack

Each creature you control that's a Wolf or a Werewolf enters with an additional +1/+1 counter on it.
−2: Create a 2/2 green Wolf creature token.

Forest

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Wolfwillow Haven

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.
{4}{G}, Sacrifice Wolfwillow Haven: Create a 2/2 green Wolf creature token. Activate only during your turn.

Wicked Wolf

When Wicked Wolf enters, it fights up to one target creature you don't control.
Sacrifice a Food: Put a +1/+1 counter on Wicked Wolf. It gains indestructible until end of turn. Tap it.

Ferocious Pup

When Ferocious Pup enters, create a 2/2 green Wolf creature token.

Spectral Hunt-Caller

{5}{G}: Creatures you control get +1/+1 and gain trample until end of turn.

Wolf's Quarry

Create three 1/1 green Boar creature tokens with "When this creature dies, create a Food token." (A Food token is an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Bounding Wolf

Fierce Witchstalker

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Fierce Witchstalker enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Packsong Pup

At the beginning of combat on your turn, if you control another Wolf or Werewolf, put a +1/+1 counter on Packsong Pup.
When Packsong Pup dies, you gain life equal to its power.

Thriving Grove

Thriving Grove enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.