One of the aspects of the Birthright setting I find so appealing is that the source material is often purposefully (or so I choose to believe) a little vague, ambiguous, or even downright contradictory. Each of these instances is an opportunity for DMs to customize the setting a little bit, based on how their interpretations.

Although I believe canon is important when discussing the official version of Cerilia, there's something to be said for deviating from canon in order to create a fun adventure or campaign plot twist. In doing so, we create our on customized version of Cerilia.

For example, in my version of Cerilia, I decided that the temples of Cuiraecen who embraced the "War for war's sake" philosophy are, in actuality, promoting the teachings of Belinik. Only temples who embraced the "protect the weak" philosophy were truly Cuiraecen's temples.

I decided that priests belonging to the Almighty Temple of Belinik (a temple controlled by a lacky of The Raven) have been instructed to infiltrate temples of Cuiraecen in Anuire and to spread the "War for war's sake" heresy. These temples would effectively be subverted to Belinik and served as the opening moves of a coordinated invasion of Anuire by the Raven, Magian, and the Gorgon. At the beginning of the campaign, approximately half of the Temple of Storm Heights has been converted (the half supporting Jaison Ranech), all of the Hidden Temple of Cuiraecen in Boerune had been converted, and the segment of the Militant Order of Cuiraecen under the leadership of Stiele Gheiste in Ghore had also been converted.

This created a fun scenario where the player character regents had to work together in order to survive.

Does anyone else have any fun examples of campaigns you participated in (either as a DM or as a player) where a particular aspect of canon was turned on its head, creating a unique and fun experience for everyone involved?

I am not looking to judge anyone who responds to this question. Rather, I think it might be helpful to provide examples for DMs who come to this site in order to be inspired.