Banshee, The Untamable

Partner with Carter Slade, Gravedigger

Soulbond with Carter Slade (You may pair this creature with a "Carter Slade" creature when either enters the battlefield. They remain paired for as long as you control both of them)

As long as this card is paired with another creature, each of those creatures has haste and "{t}: This creature deals 1 damage to any target and itself"

Whenever a creature you control transforms,
transform this creature.