Bloodsworn Squire
Creature — Vampire Soldier
{1}{B}, Discard a card: Bloodsworn Squire gains indestructible until end of turn. Tap it. Then if there are four or more creature cards in your graveyard, transform Bloodsworn Squire. (Damage and effects that say "destroy" don't destroy it.)
Bloodsworn Knight
Creature — Vampire Knight
Bloodsworn Knight's power and toughness are each equal to the number of creature cards in your graveyard. {1}{B}, Discard a card: Bloodsworn Knight gains indestructible until end of turn. Tap it. (Damage and effects that say "destroy" don't destroy it.)