The List

Spectral Gateguards

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as this creature is paired with another creature, both creatures have vigilance.

Duel Decks: Blessed vs. Cursed

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
As long as Spectral Gateguards is paired with another creature, both creatures have vigilance.