Castlevania / GAME HISTORY

Castlevania Can Freeze When a Potion Meets a Door

NESdev users reported Castlevania freezing when Simon crossed a door during potion invincibility.

By Patchlo Editorial Desk · Published October 28, 2026 · Sources checked October 28, 2026

Scope: The NES potion-and-door reports, including the 2015 NESdev discussion. Separate from the previously covered Death-fight NMI crash.

The door before Frankenstein appears in the reports

On July 11, 2015, Optomon described the game locking when passing a door while potion invincibility was active, especially at the door before Frankenstein. DRW replied that it was the same door in their case, but could not confirm having the item.

The distinction matters: the second reply corroborates the location, not every part of the potion setup. The thread title mentions PRG1, but that alone does not establish the revision used in each participant’s individual observation.

The reported overlap

These steps describe the combination players reported rather than a newly tested frame-perfect recipe.

1. Obtain the invincibility potion near a stage-transition door.
2. Cross the door while the potion effect is still active.
3. With the reported timing, the game locks during the transition.

The interrupted run and the evidence limit

The original NES game does not offer a normal save-file recovery screen. A freeze can therefore end the current attempt; emulation may permit returning to an earlier safe state if one already exists.

Waiting for the potion effect to end before entering a door is a precaution aimed at that overlap, not a certified software fix. The checked discussion does not prove that two conflicting memory banks cause it, or that the Death-fight explanation applies unchanged. No final corrected revision is established by these reports.