Innately knows the "Vermillion Sands" tech. Triggers Showstopper at critical health. On Showstopper: increases Size, reduces Max HP and Cooldown.

Door is a conditionally viable character. More effective in goal-focused runs or special stages than general builds. Key is leveraging the starter weapon (Blood Chalice) characteristics.

Intentionally build around the starter (Blood Chalice). Generic passives alone underperform — pick to match the character's identity.