Konami has warned people playing Metal Gear Solid 5: The Phantom Pain about a potentially game-breaking bug which is affecting all versions of the game on PS4, Xbox One, PC, PS3 and Xbox 360.
The bug relates to missions 29 and 42 and occurs if the player has sniper character Quiet accompany them as an AI buddy. On Konami's official Metal Gear Solid portal they offer no further details and only suggest not using Quiet as a buddy.
In Metal Gear Solid V: The Phantom Pain which was released on 1 September 2015 there is a possibility that the game stops progress if having Quiet as a buddy while playing "Mission 29" or "Mission 42". This situation can be avoided by not using Quiet as a buddy while playing either "Mission 29" or "Mission 42".
We deeply apologise, and appreciate your patience for further announcements regarding this issue.
If you utilise Quiet on these missions there is still only a chance of your game breaking, it is not a certainty, but given there are only a handful of possible AI companions in the game (and Quiet's usefulness compared to certain others) there is a high chance a lot of players will take her along.
A fix is likely being worked on and will be released in the near future as a patch, though none of this has been confirmed as of yet.
Metal Gear Solid 5: The Phantom Pain has been a big success for Konami critically and commercially, with big week one sales being confirmed. In the UK it reported the third biggest launch of the year so far and the largest for the series to date, based on data collected without digital download figures.