Getting

Cat Soldier

Ajani's Sunstriker

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Have

Felidar Retreat

Landfall — Whenever a land you control enters, choose one —
• Create a 2/2 white Cat Beast creature token.
• Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.

Cat Beast

Regal Caracal

Other Cats you control get +1/+1 and have lifelink. (Damage dealt by those creatures also causes you to gain that much life.)
When this creature enters, create two 1/1 white Cat creature tokens with lifelink.

Don't Have

Ajani's Chosen

Whenever an enchantment you control enters, create a 2/2 white Cat creature token. If that enchantment is an Aura, you may attach it to the token.

Cat Collector

When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Whenever you gain life for the first time during each of your turns, create a 1/1 white Cat creature token.

Food

{2}, {T}, Sacrifice this token: You gain 3 life.

Leonin Skyhunter

Claws Out

Affinity for Cats (This spell costs {1} less to cast for each Cat you control.)
Creatures you control get +2/+2 until end of turn.

Pride Guardian

Defender
Whenever this creature blocks, you gain 3 life.

Ajani, Wise Counselor

+2: You gain 1 life for each creature you control.
−3: Creatures you control get +2/+2 until end of turn.
−9: Put X +1/+1 counters on target creature, where X is your life total.

Ajani's Pridemate

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

Leonin Vanguard

At the beginning of combat on your turn, if you control three or more creatures, this creature gets +1/+1 until end of turn and you gain 1 life.

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Arahbo, the First Fang

Other Cats you control get +1/+1.
Whenever Arahbo or another nontoken Cat you control enters, create a 1/1 white Cat creature token.

Plains

Brimaz, King of Oreskos

Vigilance
Whenever Brimaz attacks, create a 1/1 white Cat Soldier creature token with vigilance that's attacking.
Whenever Brimaz blocks a creature, create a 1/1 white Cat Soldier creature token with vigilance that's blocking that creature.