A Fusion with "Dishonored", a video game developed by Arkane Studios and Developed by Bethesda Softworks.

Shining Armour returns home after months at sea, bearing ill news for Empress Cadence. There will be no help for Equestria - the plague that has been killing thousands, and the rats that have come with it, are to devour what is left of the great nation.
But, as Shining Armour soon discovers, Rats are not carrying the worst plague of the city.
And now, he must choose - to allow himself to resemble those he fought against, becoming a force of vengeance; or follow a path that his sister Twilight would want him to, showing that there can be -