Erector of Strongholds

When Erector of Strongholds enters the battlefield, create X colorless 0/1 Castle Worker creature tokens with defender.
{t}, {x}, Sacrifice X Castle Workers: create a colorless 0/X Castle creature token with "At the beginning of your upkeep, you may tap any number of creatures. For the duration of the combat phase, those creatures are garrisoned. (Garrisoned creatures have indestructible and hexproof.) Destroy all garrisoned creatures if Castle leaves the battlefield."