Minion creatures get +1/+1.

, Exile Balthor the Defiled: Each player returns all black and all red creature cards from their graveyard to the battlefield.

Whenever one or more cards leave your graveyard, create a 2/2 black Horror enchantment creature token. This ability triggers only once each turn.

(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)