Cooped Up

Enchant creature
Enchanted creature can't attack or block.
{2}{W}: Exile enchanted creature.

Rebellious Strike

Target creature gets +3/+0 until end of turn.
Draw a card.

Helpful Hunter

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.

Prideful Parent

Vigilance (Attacking doesn't cause this creature to tap.)
When this creature enters, create a 1/1 white Cat creature token.

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.

Savannah Lions

Leonin Surveyor

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
During your turn, this creature has first strike.
Max speed — {3}, Exile this card from your graveyard: Draw a card.

Crusader of Odric

Crusader of Odric's power and toughness are each equal to the number of creatures you control.

Skyknight Squire

Whenever another creature you control enters, put a +1/+1 counter on this creature.
As long as this creature has three or more +1/+1 counters on it, it has flying and is a Knight in addition to its other types.

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 Pridemate

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

Plains

Spellbook Vendor

Vigilance
At the beginning of combat on your turn, you may pay {1}. When you do, create a Sorcerer Role token attached to target creature you control. (If you control another Role on it, put that one into the graveyard. Enchanted creature gets +1/+1 and has "Whenever this creature attacks, scry 1.")

Felidar Savior

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
When this creature enters, put a +1/+1 counter on each of up to two other target creatures you control.

Dawnwing Marshal

Flying
{4}{W}: Creatures you control get +1/+1 until end of turn.

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.

Coordinated Maneuver

Choose one —
• Coordinated Maneuver deals damage equal to the number of creatures you control to target creature or planeswalker.
• Destroy target enchantment.

Focus Fire

Focus Fire deals X damage to target attacking or blocking creature, where X is 2 plus the number of creatures and/or Spacecraft you control.