User blog comment:Master Sima Yi/Assassinews 08-10-'13 — Freedom Cry trailer released/@comment-4999424-20131008195859/@comment-1153722-20131008200336

A trailer is a promotional video, not a finalized product. It is used to explain, summarize and tease the story, not tell it in full. It's not canon because only the actual products are canon, but it does not give us non-canon information.