Project Sekai: Colorful Stage feat. Hatsune Miku

Project Sekai is set in the real world, specifically in the city of Tokyo, Japan. In this game, Hatsune Miku and her friends are famous fictional singers exist in the real world as Virtual Singer. They sing songs from creators all over the world, but they also exist in "Sekai", a mysterious world different from the real world that created from person's "true feelings", featuring various visual appearances based on the person. There are as many Sekai as there are emotions, and its form changes depending on the person's emotions. Therefore, the focus of the game is on the original characters and their journey to find their "true feelings" with the help of the Virtual Singers.[2]

In order to enter Sekai, they are required to find and play the song "Untitled". These silent songs have no melody or lyrics and are created at the same time as the Sekai, which was mysteriously inserted on their devices, such as a post-7th generation game consoles, smartphones, smartwatches, smart TVs, tablets, or computers. As they playing an "Untitled" song, they can travel between the real world and Sekai using "Untitled" songs.

Each of the five groups has their own story, focusing on their journey to convey their true feelings:

• Leo/need: Ichika Hoshino wishes to shares her memories to make her childhood friends together again as their friendships between them has been strained in the aftermath of an incident that occurred during middle school. She entered Sekai and met Miku in an emo-punk look, who told her to convey her feelings with her friends to overcome their differences.
• More More Jump!: Minori Hanasato has always dreamed of becoming an idol. Despite having failed auditions multiple times, she never gives up and hopes to pass an audition once again. She later entered Sekai and met Miku in an idol-like look, who encourages her to make her dream come true alongside with three former idols, who retired from their career due to problems with their agency.
• Vivid Bad Squad: Kohane Azusawa who deeply passionate about street music as she stumbles upon a jam session with An Shiraishi and her male fellow musicians, Akito Shinonome and Touya Aoyagi. Captivated by their music, Kohane joined her unit to become a street musician as well as she entered Sekai and met Miku in a hip-hop look, leading Kohane and her friends to surpass the legends.
• Wonderland x Showtime: Tsukasa Tenma has been working hard to restore his sister's friendship following an incident during middle school. At some point, Tsukasa was hired to work part-time at a theme park, but the once-famous Phoenix Wonderland Stage he was assigned has been deserted to draws no customers. Then he met Emu Ootori, who wants to restore the theatre to its former glory. Joined by Nene Kusanagi and Rui Kamishiro, they formed a musical theater troupe as they entered Sekai and met a clown-like Miku, hoping to revive the theatre's glory to make peoples happy.
• 25-ji, Night Code de.: Kanade Yoisaki has been homeschooled and suffered by trauma as a result of an incident in the past. She formed an underground music circle with her online friends and communicates with each other over a voice chat app named 'Night Code', until she stumbles upon Sekai and met Miku in a gothic look, who believed she could understand their feelings, she told Kanade and her circle members to unaware of each others' identity to another.

After the introduction movie, the player must choose one of five orbs three times. If they choose all same color orbs or two same color orbs, the game will automatically reveal a group (e.g. if player choose all blue orbs, it will revealing Leo/need). However, should player choose different color all orbs, it will randomly reveal a group. But the player can freely choose another group if their choice is unsatisfactory.

There's three types stories: the main story focused group's storyline, which all chapters must unlocked by leveling group's levels. Side story focused entirely on any individual character which first part must required item to watch episode and second part must unlocked by leveling character's card in addition item requirement. And time-limited events story, which required through playing the event. There's both standalone and mixed stories: standalone stories focusing group's story like 25-ji, Night Code de. "Captivate Marionette" revolving Kanade become worry after Mafuyu develop psychotic personality after she saw a creepy doll and Vivid Bad Squad "Period of Nocturne" revolving Touya must convince his father allow him playing street music as long he continue Aoyagi family legacy. While mixed stories focusing different characters in one story like "Sekai's Happy New Year" revolving all characters celebrate new year's.[3]

The characters are divided into five groups of four, each with a theme related to the groups' backstory, complete with Hatsune Miku in a thematic attire to sing alongside them, and another Virtual Singer if available. While only characters involved in the plot are mentioned, some songs in the game feature Virtual Singers from different Sekais.

Project Sekai's gameplay consists of tapping notes as they slide toward the bottom to the rhythm of a chosen song; players have to tap, slide and flick to match new free-form rhythm notes, and special yellow notes that activate character skills and lines mid-performance. Players are given 1,000 health points to clear a song, but one can adjust song speed, difficulty, and note size to their liking. In lieu of a energy system that is prevalent in most free-to-play games, Project Sekai utilizes Live Boosts that increases rewards for completing a song, and players can continue playing even when they run out of boosts.

The game will feature multiple VOCALOID songs, which players can switch between the original versions and Project Sekai versions. Virtual Singers will perform the originals songs, while original characters joined by a Virtual Singer will sing Project Sekai’s versions. Some songs included 3DPVs, but players can switch to a 2D background if they want and not every song will have a 3DPV. This is because there's a huge variety of VOCALOID songs and not every song can be accompanied by dancers, 3DPVs are saved for more fast-paced songs.

Players gain experience points (EXP) by clearing songs and listening to overworld conversations between characters. Such talks are fully voiced with 2.5D movement via Live2D technology, and their conversations are depicted in a visual novel-style presentation that prepared for each unit, including the Virtual Singers such as Miku. Further dialogues can be attain by improving cards and attaining more EXP. EXP also improves a band's rank, which unlocks additional chapters in band stories. Cards, which use a star ranking system to determine rarity (four stars being the rarest), are acquired via the gacha system, a luck-based mechanic in which players spend the in-game currency Crystals with the hope of winning their desired cards. Although Project Sekai is a free-to-play game, players can spend real-life money to acquire more crystals.

The game also featured the Virtual Live, a mode where you can go to a virtual concert, similar to augmented reality or a Vocaloid's live concert, where players can interact with one another. You can see players all around the world and your favorite group performing via Live2D animation. The game added some contents included an overworld lounge that features original character interactions and animations and a "rehearsal" mode that allows players to practice songs without fearing health depletion.

The game was first announced on August 30, 2019 at Magical Mirai 2019.[4] The development is done by the Colorful Palette, a newly established subsidiary of Craft Egg (who is already known for another rhythm game: BanG Dream! Girls Band Party). Yuichiro Kondo, the first producer of Girls Band Party, also serves as the producer for this game. The project started in 2017 and was initially being developed entirely by Craft Egg, but Kondo thought it was necessary to avoid a situation where the project would clash with the development of Girls Band Party, so he created Colorful Palette with Craft Egg's core members within the company.[5][6][7]

The title is a rhythm game that features arrangements of songs made by various artists over the years using the Vocaloid software. The original story of the game is told in a visual novel style. The direction of the game's design and concept is different from Hatsune Miku-related games, such as Sega's Hatsune Miku: Project DIVA, where the player and Hatsune Miku face each other directly and communicate in the game. The project is said to be "a work that embodies the existence of Hatsune Miku" and explores the relationship between music and people. One of the reasons behind this format was the idea of "wanting the younger generation to listen to more Vocaloid music and other songs from the internet." Therefore, while knowing that there could be people opposed to the idea of addition of original characters, it was decided to develop such setting.[8]

Project Sekai's pre-registration was originally set to begin in late April, but was delayed until further notice due to the COVID-19 pandemic. The pre-registration later started on July 22, and Sega revealed the goals were set from 100,000 to 1,000,000 pre-registrations. In September 2020, the pre-registrations later reached 1,000,000 and players who pre registered received rewards.

Despite the game being released only in Japanese, the staff is gradually starting to consider an overseas release in the future.

• BanG Dream! Girls Band Party! — Another game developed by Craft Egg
• Crypton Future Media
• Vocaloid

• Official website (in Japanese)