Gatstaf Howler

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Gatstaf Howler.

Gatstaf Shepherd

At the beginning of each upkeep, if no spells were cast last turn, transform Gatstaf Shepherd.

Gatstaf Shepherd // Gatstaf Howler

Krallenhorde Killer

{3}{G}: Krallenhorde Killer gets +4/+4 until end of turn. Activate only once each turn.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Krallenhorde Killer.

Wolfbitten Captive

{1}{G}: Wolfbitten Captive gets +2/+2 until end of turn. Activate only once each turn.
At the beginning of each upkeep, if no spells were cast last turn, transform Wolfbitten Captive.

Wolfbitten Captive // Krallenhorde Killer

Grapple with the Past

Mill three cards, then you may return a creature or land card from your graveyard to your hand. (To mill three cards, put the top three cards of your library into your graveyard.)

Howling Chorus

Creatures with power less than Howling Chorus's power can't block it.
Whenever Howling Chorus deals combat damage to a player, create a 3/2 colorless Eldrazi Horror creature token.

Shrill Howler

Creatures with power less than Shrill Howler's power can't block it.
{5}{G}: Transform Shrill Howler.

Shrill Howler // Howling Chorus

Cult of the Waxing Moon

Whenever a permanent you control transforms into a non-Human creature, create a 2/2 green Wolf creature token.

Skalla Wolf

When Skalla Wolf enters, look at the top five cards of your library. You may reveal a green card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Pack Guardian

Flash (You may cast this spell any time you could cast an instant.)
When Pack Guardian enters, you may discard a land card. If you do, create a 2/2 green Wolf creature token.

Moonmist

Transform all Humans. Prevent all combat damage that would be dealt this turn by creatures other than Werewolves and Wolves. (Only double-faced cards can be transformed.)

Fang of the Pack

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
At the beginning of combat on your turn, another target creature you control gains melee until end of turn. (If a creature has multiple instances of melee, each triggers separately.)

Werewolf of Ancient Hunger

Vigilance, trample
Werewolf of Ancient Hunger's power and toughness are each equal to the total number of cards in all players' hands.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Werewolf of Ancient Hunger.

Sage of Ancient Lore

Sage of Ancient Lore's power and toughness are each equal to the number of cards in your hand.
When Sage of Ancient Lore enters, draw a card.
At the beginning of each upkeep, if no spells were cast last turn, transform Sage of Ancient Lore.

Sage of Ancient Lore // Werewolf of Ancient Hunger

Vivien, Arkbow Ranger

+1: Distribute two +1/+1 counters among up to two target creatures. They gain trample until end of turn.
−3: Target creature you control deals damage equal to its power to target creature or planeswalker.
−5: You may reveal a creature card you own from outside the game and put it into your hand.

Vivien, Champion of the Wilds

You may cast creature spells as though they had flash.
+1: Until your next turn, up to one target creature gains vigilance and reach.
−2: Look at the top three cards of your library. Exile one face down and put the rest on the bottom of your library in any order. For as long as it remains exiled, you may cast it if it's a creature spell.

Shapers' Sanctuary

Whenever a creature you control becomes the target of a spell or ability an opponent controls, you may draw a card.

Emergence Zone

{T}: Add {C}.
{1}, {T}, Sacrifice Emergence Zone: You may cast spells this turn as though they had flash.

Sinuous Predator

Sinuous Predator can't be blocked by more than one creature.

Kessig Prowler

Kessig Prowler // Sinuous Predator

Moonscarred Werewolf

Vigilance
{T}: Add {G}{G}.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Moonscarred Werewolf.

Scorned Villager

{T}: Add {G}.
At the beginning of each upkeep, if no spells were cast last turn, transform Scorned Villager.

Scorned Villager // Moonscarred Werewolf

Ulvenwald Abomination

Ulvenwald Captive

Defender
{T}: Add {G}.
{5}{G}{G}: Transform Ulvenwald Captive.

Ulvenwald Captive // Ulvenwald Abomination

Rampant Growth

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

Waxing Moon

Transform up to one target Werewolf you control. Creatures you control gain trample until end of turn.

Forest

Howlpack Alpha

Each other creature you control that's a Werewolf or a Wolf gets +1/+1.
At the beginning of your end step, create a 2/2 green Wolf creature token.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Howlpack Alpha.

Mayor of Avabruck

Other Human creatures you control get +1/+1.
At the beginning of each upkeep, if no spells were cast last turn, transform Mayor of Avabruck.

Mayor of Avabruck // Howlpack Alpha

Cryptic Caves

{T}: Add {C}.
{1}, {T}, Sacrifice Cryptic Caves: Draw a card. Activate only if you control five or more lands.

Witchstalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Whenever an opponent casts a blue or black spell during your turn, put a +1/+1 counter on Witchstalker.

Great Oak Guardian

Flash (You may cast this spell any time you could cast an instant.)
Reach
When Great Oak Guardian enters, creatures target player controls get +2/+2 until end of turn. Untap them.

Pounce

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

Krallenhorde Howler

Creature spells you cast cost {1} less to cast.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Krallenhorde Howler.

Duskwatch Recruiter

{2}{G}: Look at the top three cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.
At the beginning of each upkeep, if no spells were cast last turn, transform Duskwatch Recruiter.

Duskwatch Recruiter // Krallenhorde Howler

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.

Spirit of the Hunt

Flash
When Spirit of the Hunt enters, each other creature you control that's a Wolf or a Werewolf gets +0/+3 until end of turn.

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.

Silverfur Partisan

Trample
Whenever a Wolf or Werewolf you control becomes the target of an instant or sorcery spell, create a 2/2 green Wolf creature token.

Wolfir Silverheart

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Wolfir Silverheart is paired with another creature, each of those creatures gets +4/+4.

Natural Connection

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

Lone Wolf of the Natterknolls

Whenever an opponent casts a spell during your turn, draw two cards.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Lone Wolf of the Natterknolls.

Hermit of the Natterknolls

Whenever an opponent casts a spell during your turn, draw a card.
At the beginning of each upkeep, if no spells were cast last turn, transform Hermit of the Natterknolls.

Hermit of the Natterknolls // Lone Wolf of the Natterknolls

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Titanic Brawl

This spell costs {1} less to cast if it targets a creature you control with a +1/+1 counter on it.
Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Nightpack Ambusher

Flash
Other Wolves and Werewolves you control get +1/+1.
At the beginning of your end step, if you didn't cast a spell this turn, create a 2/2 green Wolf creature token.

Leyline of Vitality

If Leyline of Vitality is in your opening hand, you may begin the game with it on the battlefield.
Creatures you control get +0/+1.
Whenever a creature you control enters, you may gain 1 life.

Briarpack Alpha

Flash (You may cast this spell any time you could cast an instant.)
When Briarpack Alpha enters, target creature gets +2/+2 until end of turn.

Howlpack Resurgence

Flash (You may cast this spell any time you could cast an instant.)
Each creature you control that's a Wolf or a Werewolf gets +1/+1 and has trample.