The end credits reference a movie based on the game's events
- In The Battle of Old Castle game book, Christopher Bee is an actor playing Dracula in the Castlevania movie. The movie is a documentary describing the events of the game.
- The first three NES games have a film strip intro, implying a trilogy of movies based on the actual events. Haunted Castle, Castlevania Chronicles, Castlevania IV, Lord of Shadow, or the anime may be more accurate versions of events.
- Made in the modern era, Soma Cruz and Genya Arikado should be able to view these movies and verify how accurate they may be.
Simon defeats Dracula more than once
Simon goes through the castle and defeats Dracula in Haunted Castle, Castlevania MSX, Castlevania NES, Castlevania Chronicles and Super Castlevania IV. They are not reboots or remakes, but are each separate attempts to take down Dracula. Each version of the first game's events are a parallel reality
Simon defeats Dracula in alternate realities chronicling the same event, including Haunted Castle, Castlevania IV, and Castlevania Chronicles. The Wall Chicken isn't really a chicken.
It's a bird that got stuck inside the wall and died. It looks like a roast chicken because Belmont is starving after fighting his way through a monster filled castle for who knows how long.