| Purpose | Tool | |---------|------| | Metadata viewer | ExifTool, Jeffrey’s Image Metadata Viewer | | Steganography | StegHide, zsteg (for PNGs) | | Hex editor | HxD, HexEdit | | ePub unpacker | Calibre, Sigil, or simply unzip | | ARG community help | Reddit r/arg, r/uketsu (if Japanese mystery) |

: Originally a massive hit in Japan, an English translation by Jim Rion was released in the United States in early 2025 by HarperVia and Pushkin Vertigo in the UK. Plot Summary (Non-Spoiler)

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