Where Assassin’s Creed is based on tracing back the character’s DNA and lineage to recreate and discover a combination of historically accurate moments mixed with the game’s narrative, this DLC appears to be completely fictional. Thanks to Games On Net, who have the trailer or it can be viewed below.
The fictional slant on the story is apparently to avoid fracturing the audience and therefor making it easier to keep up with the canon of the series.
A synopsis and details of the DLC are available here, which, as seen in the trailer include knight style armoured guards with rifles. One can only wonder how Connor will be able to take these guards out, even with a wolf at his side.