User blog comment:LilyheartsLightning/Author Ex Maraudia — A Review of Marauder Shields/@comment-101.168.255.254-20121228111051/@comment-24174486-20121228124345

While some events will play out differently based on your choices (or, based on your choices, not play out at all), there are events which will always happen. There isn't a strict canon, but in all playthroughs Shepard always does certain things and side characters always have the same personality. There's no playthrough in which you can not do the Collector Base or Priority: Cerberus Headquarters, for example. The latter is important regarding this review, because that means that there is no playthrough where you can have a Shepard who doesn't alert a VI's indoctrination detector immediately before the final mission. Likewise, there is no playthrough you can do where Harbinger doesn't constantly try to kill Shepard.