Cathar's Companion

Whenever you cast a noncreature spell, Cathar's Companion gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Alpine Watchdog

Vigilance (Attacking doesn't cause this creature to tap.)

Trusty Retriever

When Trusty Retriever enters, choose one —
• Put a +1/+1 counter on Trusty Retriever.
• Return target artifact or enchantment card from your graveyard to your hand.

Secure the Scene

Exile target nonland permanent. Its controller creates a 1/1 white Soldier creature token.

Supply Runners

When Supply Runners enters, put a +1/+1 counter on each other creature you control.

Plains

Pacifism

Enchant creature
Enchanted creature can't attack or block.

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.

Selfless Savior

Sacrifice Selfless Savior: Another target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Affa Guard Hound

Flash (You may cast this spell any time you could cast an instant.)
When Affa Guard Hound enters, target creature gets +0/+3 until end of turn.

Feat of Resistance

Put a +1/+1 counter on target creature you control. It gains protection from the color of your choice until end of turn. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything of that color.)

Release the Dogs

Create four 1/1 white Dog creature tokens.

Rambunctious Mutt

When Rambunctious Mutt enters, destroy target artifact or enchantment an opponent controls.

Thriving Heath

Thriving Heath enters tapped. As it enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.