{"rewrite":{"id":"r_c1a7723ef1b9a18465732e21","clusterId":"c_3641a9de3f17afd81804cb7c","slug":"project-sekai-adds-vivid-bad-squad-s-seikai-as-rhythm-game-song","model":"deepseek-v4-flash","headline":"Project Sekai Adds Vivid BAD SQUAD's Seikai as Rhythm Game Song","summary":"Vivid BAD SQUAD's unit song \"Seikai\" was added to Project Sekai: Colorful Stage! feat. Hatsune Miku as a rhythm game song on September 6, 2026, available to anyone from the in-game Present section. The lineup also includes \"Kyofu All Back,\" \"Kofukukei,\" \"Haneuta,\" and \"Pentatonic.\" The event \"After the Fire\" and the \"Shady Stare Gacha\" are running alongside it.","whyItMatters":"The song arrives as part of a wider September content push, since the same update carries the After the Fire event, its After Live, and the Shady Stare Gacha, so the rhythm track is one piece of a package aimed at keeping Vivid BAD SQUAD players inside the game.","webCardHtml":"\u003cp\u003e\u0026#34;Seikai\u0026#34; can be picked up from the Present section, and the Sekai ver.\u0026#39;s 2DMV is viewable by choosing 2DMV from the member confirmation screen in MV Viewing or from a Live\u0026#39;s final confirmation screen. Another Vocal versions come through Vocal Cards at the Another Vocal Shop: one sung by Emu Otori (CV. Hina Kino), plus two sung by MEIKO and Kanade Yoisaki (CV. Tomori Kusunoki). The event runs through September 12, with Event P and Event Badges earned across Solo Live, Multi Live, Challenge Live, and Rank Match, and from stamina spent gathering in My Sekai.\u003c/p\u003e","blueskyPost":"Seikai joins Project Sekai free from the Present section, while After the Fire and the Shady Stare Gacha run beside it. The song is the hook; the event window is what keeps players logged in.","twitterPost":"Project Sekai gives Seikai away free in the Present section while After the Fire runs. The song pulls players in; the event window keeps them.","threadsPost":"Project Sekai adds Vivid BAD SQUAD's Seikai to the rhythm game and hands it out free from the Present section, with After the Fire and the Shady Stare Gacha running alongside. A free unit song is a retention tool as much as a content drop, and the event calendar is doing the real work.","newsletterBlurb":"Project Sekai added Vivid BAD SQUAD's \"Seikai\" as a rhythm game song on September 6, free to claim from the Present section. Another Vocal versions are available through Vocal Cards, including one sung by Emu Otori and two sung by MEIKO and Kanade Yoisaki. The \"After the Fire\" event and the \"Shady Stare Gacha\" run alongside the song.","attributionJson":"[{\"source\":\"Nijimen\",\"url\":\"https://nijimen.kusuguru.co.jp/topics/635000\",\"title\":\"\\\"Project Sekai\\\" Adds \\\"Seikai\\\" as a Rhythm Game Song! Event \\\"After the Fire\\\" Runs Until September 12\"}]","lintFlagsJson":null,"lintHits":0,"costUsd":0,"inputTokens":4861,"outputTokens":698,"status":"published","repairAttempts":0,"nextRepairAt":null,"factsAttemptedAt":1789100970,"createdAt":"2026-09-11T04:24:12.000Z","publishedAt":"2026-09-11T04:28:22.000Z","updatedAt":"2026-09-11T04:28:22.000Z"},"cluster":{"id":"c_3641a9de3f17afd81804cb7c","canonicalTitle":"『プロセカ』「正解」がリズムゲーム楽曲に追加！イベント「After the Fire」は9月12日まで開催中","representativeArticleId":"a_ea4ffc7d2462f28662eb5a4d","sourceCount":1,"writtenSourceCount":1,"writeAttempts":0,"isSolo":true,"entitiesJson":"{\"anime_titles\":[],\"manga_titles\":[],\"work_titles\":[\"Project Sekai: Colorful Stage! feat. Hatsune Miku\"],\"studios\":[\"Sega\",\"Colorful Palette\"],\"people\":[],\"type\":\"news\",\"domain\":\"games\",\"is_roundup\":false}","contentType":"news","status":"published","firstSeenAt":"2026-09-11T03:36:16.000Z","lastSeenAt":"2026-09-11T03:36:16.000Z","updatedAt":"2026-09-11T04:28:20.000Z"},"attribution":[{"source":"Nijimen","url":"https://nijimen.kusuguru.co.jp/topics/635000","title":"『プロセカ』「正解」がリズムゲーム楽曲に追加！イベント「After the Fire」は9月12日まで開催中"}],"entities":{"anime_titles":[],"manga_titles":[],"work_titles":["Project Sekai: Colorful Stage! feat. Hatsune Miku"],"studios":["Sega","Colorful Palette"],"people":[],"type":"news","domain":"games","is_roundup":false},"keyFacts":null}