Hidetaka Miyazaki’s games are known for their fiendish difficulty levels, but his latest, ‘Bloodborne’, has taken the unintended further step of including a serious progression bug.

On 27 March, Sony Computer Entertainment confirmed in an email to the multimedia site Polygon that a game item called the ‘Lunarium Key’ went missing if a player initiated a multiplayer session in the game’s Forbidden Woods area. Without the key, several other game areas, characters and enemies are inaccessible.

Sony said that the game’s developers, From Software, were working on a hotfix, which would appear within the next week. Until then, players were advised to avoid multiplayer sessions in the Forbidden Woods.

‘Bloodborne’ is exclusive to Sony’s Playstation 4 console and it is an important title in the system’s efforts to retain its early sales lead over Microsoft’s Xbox One. Prior to the discovery of the bug, ‘Bloodborne’ received excellent reviews from critics, with one comparing it to a ‘descent into madness’.

However, critics also noted the long loading times and inconsistent frame rates. In its email, Sony added that the hotfix would not include any improvements to load times and performance, which would instead be included in a separate patch.