The key card is present but its support is thin.
Prioritize useful support such as Overgrown Zealot or Manifest Dread.
Develop Oblivious Bookworm, then manifest dread during your turn so its end-step draw need not discard. Overgrown Zealot's special two mana helps turn a creature face up later, which also satisfies Bookworm.
Your deck enables the plan but is losing the early turns.
Take a castable early creature or efficient answer before another expensive payoff.
Manifested creatures have no inherent ward. Turning one face up is a special action, not casting or entering again, and normal turn-up requires a creature card with a payable mana cost.
The support is missing
Favor independently useful creatures and interaction if the narrow support does not arrive.