Lord Aethelstan, Hell Knight

Domain Castle —When Lord Aethelstan, Hell Knight enters the battlefield, create a legendary 0/12 artifact land creature token with defender, flying and "{t}: Add {1}."

Blood Vial Necklace —On every player's upkeep,
choose one —
•Create a Blood token.
•Destroy X Blood tokens, Lord Aethelstan, Hell Knight gets +X/+X.

"When God himself removes your light, remember
that true darkness breeds the Knight."