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

Immerwolf

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Each other creature you control that's a Wolf or a Werewolf gets +1/+1.
Non-Human Werewolves you control can't transform.

Feral Ridgewolf

Trample
{1}{R}: Feral Ridgewolf gets +2/+0 until end of turn.

Furor of the Bitten

Enchant creature
Enchanted creature gets +2/+2 and attacks each combat if able.

Krallenhorde Wantons

At the beginning of each upkeep, if a player cast two or more spells last turn, transform Krallenhorde Wantons.

Grizzled Outcasts

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

Grizzled Outcasts // Krallenhorde Wantons

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

Full Moon's Rise

Werewolf creatures you control get +1/+0 and have trample.
Sacrifice Full Moon's Rise: Regenerate all Werewolf creatures you control.

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.)

Forest

Ravager of the Fells

Trample
Whenever this creature transforms into Ravager of the Fells, it deals 2 damage to target opponent or planeswalker and 2 damage to up to one target creature that player or that planeswalker's controller controls.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Ravager of the Fells.

Huntmaster of the Fells

Whenever this creature enters or transforms into Huntmaster of the Fells, create a 2/2 green Wolf creature token and you gain 2 life.
At the beginning of each upkeep, if no spells were cast last turn, transform Huntmaster of the Fells.

Huntmaster of the Fells // Ravager of the Fells

Hunger of the Howlpack

Put a +1/+1 counter on target creature.
Morbid — Put three +1/+1 counters on that creature instead if a creature died this turn.

Blessings of Nature

Distribute four +1/+1 counters among any number of target creatures.
Miracle {G} (You may cast this card for its miracle cost when you draw it if it's the first card you drew this turn.)

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.)

Garruk, the Veil-Cursed

+1: Create a 1/1 black Wolf creature token with deathtouch.
−1: Sacrifice a creature. If you do, search your library for a creature card, reveal it, put it into your hand, then shuffle.
−3: Creatures you control gain trample and get +X/+X until end of turn, where X is the number of creature cards in your graveyard.

Garruk Relentless

When Garruk Relentless has two or fewer loyalty counters on him, transform him.
0: Garruk Relentless deals 3 damage to target creature. That creature deals damage equal to its power to him.
0: Create a 2/2 green Wolf creature token.

Garruk Relentless // Garruk, the Veil-Cursed

Pyreheart Wolf

Whenever Pyreheart Wolf attacks, creatures you control gain menace until end of turn. (They can't be blocked except by two or more creatures.)
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.)

Arlinn, Embraced by the Moon

+1: Creatures you control get +1/+1 and gain trample until end of turn.
−1: Arlinn, Embraced by the Moon deals 3 damage to any target. Transform Arlinn, Embraced by the Moon.
−6: You get an emblem with "Creatures you control have haste and '{T}: This creature deals damage equal to its power to any target.'"

Arlinn Kord

+1: Until end of turn, up to one target creature gets +2/+2 and gains vigilance and haste.
0: Create a 2/2 green Wolf creature token. Transform Arlinn Kord.

Arlinn Kord // Arlinn, Embraced by the Moon

Mountain

Tovolar's Magehunter

Whenever an opponent casts a spell, Tovolar's Magehunter deals 2 damage to that player.
At the beginning of each upkeep, if a player cast two or more spells last turn, transform Tovolar's Magehunter.

Mondronen Shaman

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

Mondronen Shaman // Tovolar's Magehunter

Clinging Mists

Prevent all combat damage that would be dealt this turn.
Fateful hour — If you have 5 or less life, tap all attacking creatures. Those creatures don't untap during their controller's next untap step.