Project SEKAI is a rhythm and story game centered on music, friendships, and Hatsune Miku alongside other Virtual Singers. The story moves between the real world and mysterious places called SEKAI, which are created from people’s feelings. Different groups of teenagers discover their own SEKAI and meet versions of Miku and other Virtual Singers there. Rather than following one protagonist, the game tells several connected stories about characters dealing with music, ambitions, relationships, and personal problems.

Stories and Music Groups

The main cast is divided into five groups: Leo/need, MORE MORE JUMP!, Vivid BAD SQUAD, Wonderlands×Showtime, and Nightcord at 25:00. Each group has its own storyline, musical style, characters, and version of SEKAI. Story chapters are presented with voiced dialogue, while regular events add new episodes that develop relationships and continue individual character arcs. Virtual Singers such as Hatsune Miku, Kagamine Rin, Kagamine Len, Megurine Luka, MEIKO, and KAITO appear across these stories.

Rhythm Gameplay

Songs are played by interacting with notes as they travel toward the judgment line. The main actions include:

·         tapping normal notes;

·         holding long notes;

·         flicking notes in the required direction;

·         building combos by avoiding mistakes;

·         selecting one of six difficulty levels;

·         creating a five-character team before a show;

·         earning EXP and items after completing songs;

·         watching supported songs with customizable 3DMV performances.

Accuracy determines the score and combo, while harder charts increase note speed, density, and complexity.

Progression and Game Modes

Project SEKAI does not use traditional numbered levels for its main gameplay. Progress is spread across songs, stories, character development, events, and account systems. Characters can be leveled through practice, their side stories can be unlocked, and cards provide skills that affect scoring or recovery during shows. Costumes can also be unlocked and used in compatible music videos.

Players can complete songs alone, join Co-op Shows with other players, participate in event formats, or enter Ranked Matches after meeting the required conditions. Ranked play focuses more heavily on rhythm performance, while events reward Event Points that can be exchanged for cards and other items. New songs and story events are added over time, so progression is based on improving rhythm accuracy, building character teams, reading group stories, and completing increasingly difficult charts rather than reaching a single final stage.