The game follows the Metroidvania-style gameplay of the post-Symphony of the Night games of the Castlevania series. As Miriam, the player explores a labyrinthine series of rooms presented as a platform game, fighting monsters and bosses and gaining keys or powers that let them explore previous areas that were previously impossible to reach. Miriam is able to use various weapons to perform melee or ranged attacks to defeat monsters, or special abilities granted by the shards she possesses from monsters to perform magical attacks. Miriam has both a health bar and a magic power bar. Health is lost to monster and environmental attacks, and should this drop to zero, the game is over, requiring the player to load the last save state. Health can be restored by using items or finding health drops from monsters or environmental pieces. Magic power is drained by using shard skills, and if out of mana, the player cannot use shard skills, but mana can be similarly regained as with health.
The player gains new weapons, armor and accessories throughout the game by defeating monsters and looting chests. This equipment provides various attributes to Miriam along with offensive and defensive bonuses. For weapons, this also set the type of attacks that the player can make. For example, short swords allow a variety of fast, close-ranged attacks, spears enable slow but long-reaching attacks, and guns allow for long-distance shots but with no melee possibilities. The equipment can be changed on the fly via menu screens. Shards are obtained by defeating monsters, and generally contain a power reflecting the essence of the monster it came from. The player can only equip a limited number of shards, but like equipment, shards can be swapped out on the fly.
Among the maze of rooms include save rooms, allowing the player to save their game and fully regenerate Miriam's health and magic power. Additionally, warp rooms allow the player to quick jump from one region of the map to another previously discovered warp room. Following the game's prelude, the player also gains access to a set of non-playable characters located at the start of the map that provide stores to buy and sell weapons, shards, ingredients and crafting services to make new weapons or upgrade shards. The game is presented in a 2.5D style, presenting the game in three-dimensional graphics but restricting movement to a 2D system. Igarashi stated the choice for 2.5D was to follow the style of previous Castlevania games, such as The Dracula X Chronicles and Mirror of Fate.[2][5]