A group of Far Cry 4 owners have inadvertently revealed they have pirated the game by discussing one of its glitches online.

Ubisoft has found a way to ensure that certain Far Cry 4 torrents contain an error which remove's the game's field-of-view controls. Without those controls, which are available on legitimately purchased versions, the picture can become blurred and distorted.

Now, after numerous players have publicised their grievances with this bug, a developer at Ubisoft has revealed the true reason for the problem.

Alex Hutchinson, a creative director at Ubisoft Montreal, wrote on Twitter: "PC players! If you're online complaining about the lack of FOV control ... You pirated the game."

PC players! If you're online complaining about the lack of FOV control ... You pirated the game. — Alex Hutchinson (@BangBangClick) November 18, 2014

The Far Cry 4 trick is the latest in a series of pranks that developers play on those who try to illicitly download their games.

In September, Electronic Arts spliced a bug into pirate copies of The Sims 4 where the image becomes increasingly pixellated.

Other developers have demonstrated more pleasure from dishing pirates their comeuppance. In 2010, a pirated copy of Serious Sam 3 added an invincible, giant scorpion mutant that hounded the player for the remainder of the game.