フェイクフェイス・フェイルセイフ (Fake Face Failsafe) is a maimai original song composed, arranged, and written by カラスヤサボウ (Karasuyasabou) with vocals by もるでお (Moldeo), released for maimai DX BUDDiES on December 22, 2023. The track serves as the final unlock goal of the Sky Street Area 5 (スカイストリートちほー5) chapter, part of an ongoing narrative arc following characters Akatsuki, Kohaku, Sou, Nanoha, and Momo through a story of time loops, altered memories, and butterfly-shaped scars. At 202 BPM, the song is a high-energy electronic rock piece with a relentless driving beat and intense vocal delivery. The lyrics explore deception, the "fake face" of the title, and a desperate refusal to let a loved one disappear, captured in the refrain "消えない 消せない 決して消させはしない" (won't disappear, can't erase, will never let it be erased). The background movie was created by 桜井貴志 (Takashi Sakurai) under the alias fzwrAym, complementing the song's nocturnal, neon-tinted atmosphere. In-game, the track received a full DX chart spread. The MASTER chart, designed by Jack at a 13.8 difficulty constant, packs 883 notes across all five touch types and is widely noted for its demanding slide and break-note patterns at high speed. The EXPERT chart, designed by きょむりん, drew additional attention on its Asian release when it shipped with a charting bug, a 660-note version featuring four-simultaneous-tap sections, that was corrected the following day.