Inside save rooms, in the background is a large pile of rubble. Among the rubble are the remains of Alucard's coffin from the save rooms in Symphony of the Night.

After beating the game at least once, starting a new game and entering the name "Julius" on the Name Entry screen allows the player to play as Julius Belmont.

The enemy "Triton" looks very much like the Triton fountain on the Piazza Barberini in Italy.

The "Kicker Skeleton" enemy wears a red scarf and attacks by leaping into the air with its arms outstretched, then delivering a flying kick. These two elements are a reference to the Japanese superhero, Kamen Rider, who is known for his flying-kick finishing move and his red scarf. If Soma acquires the Kicker Skeleton's soul, he will gain a flying-kick ability, and the enemy also has a chance to drop wearable "Red Scarf" and "Ancient Belt" items.

The Ancient Belt alludes to the many belts which give the Kamen Riders their powers. Its description explains that it "lends the wearer a positive attitude", a reference to Kamen Rider Kuuga, whose belt, The Arcle, was not only an artifact from an ancient civilization but who is also characterized by his unusually upbeat and optimistic personality. The "Ancient Belt" item's box-like design mirrors Kamen Rider Black's belt, the King Stone. Ironically, neither Kamen Rider Black nor Kamen Rider Kuuga wore scarves, unlike many of the early Riders.

The Killer Doll enemy's description appears to be based on Chuckie from the Child's Play movies. It reads, "A figurine possessed by the spirit of a mass murderer", which describes Chuckie in the original Child's Play movie.

A soul called "Cagnazzo" can be obtained that makes a demon appear behind the protagonist and punch wildly whilst shouting "Ora ora ora!". This is likely a reference to Star Platinum, from the manga series JoJo's Bizarre Adventure.

In an interview with game's producer, Koji Igarashi, found within the game's official Japanese strategy guide, he was asked why he set the game in Japan. He responded:

The Chronomage soul allows Soma to briefly stop time. When encountering a Red Minotaur, using the soul to stop time just before the enemy can catch the axe it threw in the air will cause the axe to fall out of bounds during the pause in time. Once time starts again, the Red Minotaur will enter an animation lock and change its AI to be more aggressive, dashing towards Soma to try and uppercut him, featuring unique sprite animations that cannot be seen otherwise.