Aya explores Manhattan through a sequence of story locations, searching for clues, speaking with characters, collecting items, and fighting enemies. Battles begin when encounters are triggered and take place in separate arenas. Aya can move freely while waiting for the Active Time Battle gauge to fill, then select weapons, armor, items, or a Parasite Energy ability from the command menu.

Weapons and armor can be modified with stored tools and bonus points, allowing players to transfer or improve attributes. Experience raises Aya's level, while equipment and inventory management strongly affect survival. The main story is divided into chapters, and completing the game unlocks an additional high-difficulty challenge in the Chrysler Building.

Use the Active Time Battle gauge to reposition before committing to an attack. Keep distance from dangerous enemies, learn attack patterns, and use healing items before Aya becomes critically injured.

Upgrade a dependable weapon and armor set rather than spreading bonus points randomly. Store useful items and tools, and inspect equipment carefully because weapon range, ammunition, and special attributes can matter as much as raw attack power.

Parasite Energy is valuable for emergency healing and elemental damage. Save powerful abilities and restorative items for bosses, and remember that the post-game Chrysler Building is substantially more demanding than the main story.