Guinness World Records now lists ProjectMoon’s Library of Ruina as the holder of “Longest videogame campaign/story”, with a main campaign of about 113 hours as of June 2026. The South Korean studio announced the record on X on 27 October, in Korean and English.
The Guinness entry says the figure is about 12 hours more than the previous holder, Persona 5 Royal (P-Studio, 2019). It does not say how the playtime was measured. AUTOMATON pointed out that the figures match the “Main Story” averages that players log on HowLongToBeat, and that the category is about story campaigns: idle and management games whose clear times run into the hundreds or thousands of hours are not comparable, so the record does not make Library of Ruina the longest game to finish overall.
Library of Ruina is a deck-building RPG told largely through visual-novel scenes. On its Steam page, players host guests in a library and fight them with librarians using cards and dice; defeated guests turn into books that help the library grow. The game entered Steam early access on 15 May 2020 and was fully released on 10 August 2021 for Windows and Xbox One, followed in 2024 by Nintendo Switch and PlayStation 4 versions published by Arc System Works, according to Wikipedia. It is the second game in ProjectMoon’s shared setting, after Lobotomy Corporation (2018) and before Limbus Company (2023), which the Guinness entry also names. The Steam version supports English, Japanese, Simplified Chinese and Korean.