Jedit Ojanen of Efrava

Forestwalk (This creature can't be blocked as long as defending player controls a Forest.)
Whenever Jedit Ojanen of Efrava attacks or blocks, create a 2/2 green Cat Warrior creature token with forestwalk.

Rin and Seri, Inseparable

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri, Inseparable deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on this creature.

Kitt Kanto, Mayhem Diva

When Kitt Kanto enters, create a 1/1 green and white Citizen creature token.
At the beginning of combat on each player's turn, you may tap two untapped creatures you control. When you do, target creature that player controls gets +2/+2 and gains trample until end of turn. Goad that creature.

Ajani, Nacatl Avenger

+2: Put a +1/+1 counter on each Cat you control.
0: Create a 2/1 white Cat Warrior creature token. When you do, if you control a red permanent other than Ajani, Nacatl Avenger, he deals damage equal to the number of creatures you control to any target.
−4: Each opponent chooses an artifact, a creature, an enchantment, and a planeswalker from among the nonland permanents they control, then sacrifices the rest.

Ajani, Nacatl Pariah

When Ajani, Nacatl Pariah enters, create a 2/1 white Cat Warrior creature token.
Whenever one or more other Cats you control die, you may exile Ajani, then return him to the battlefield transformed under his owner's control.

Ajani, Nacatl Pariah // Ajani, Nacatl Avenger

Frenzied Arynx

Riot (This creature enters with your choice of a +1/+1 counter or haste.)
Trample
{4}{R}{G}: Frenzied Arynx gets +3/+0 until end of turn.

Scrapwork Mutt

When Scrapwork Mutt enters, you may discard a card. If you do, draw a card.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Guma

Goldhound

First strike
Menace (This creature can't be blocked except by two or more creatures.)
{T}, Sacrifice Goldhound: Add one mana of any color.

Arahbo, Roar of the World

Eminence — At the beginning of combat on your turn, if Arahbo, Roar of the World is in the command zone or on the battlefield, another target Cat you control gets +3/+3 until end of turn.
Whenever another Cat you control attacks, you may pay {1}{G}{W}. If you do, it gains trample and gets +X/+X until end of turn, where X is its power.

Highcliff Felidar

Vigilance
When Highcliff Felidar enters, for each opponent, choose a creature with the greatest power among creatures that player controls. Destroy those creatures.

Pack Leader

Other Dogs you control get +1/+1.
Whenever Pack Leader attacks, prevent all combat damage that would be dealt this turn to Dogs you control.

Jazal Goldmane

First strike (This creature deals combat damage before creatures without first strike.)
{3}{W}{W}: Attacking creatures you control get +X/+X until end of turn, where X is the number of attacking creatures.

Felidar Guardian

When Felidar Guardian enters, you may exile another target permanent you control, then return that card to the battlefield under its owner's control.