Undreaming
From TLJwiki
Supposing, given that there is no evidence, that the Storytime which Gordon calls "the Dreaming" - is analogous to the Aboriginal concept of 'the Dreaming', the Undreaming is presumably the opposite - a force that undoes creation. Brian has never mentioned his encounter with the Undreaming. In fact, he actually told April Ryan in The Longest Journey that he was trapped in the Divide for three centuries (261 years). In Dreamfall, he describes himself as being unstuck in time, which suggests that he was in the Storytime instead. Given the nature of the Undreaming's attack, many have speculated that Brian is actually possessed by the Undreaming. (It is certainly odd that one of the drawings on the wall in Faith's room in Saint Petersburg seems to depict the Undreaming's attack on Brian, in enough detail to show the Vagabond's campfire.)
If true, this would appear to be the culmination of some sort of plan. The whispering monks at the Tibetan monastery mention the Undreaming, saying Brian is "perfect", clearly indicating that their plan is to send him to the Storytime to awake it. The cutscene at the end of the credits hints that Manny Chavez was also privy to this plan, whatever it involves. This has led to many people casting Brian as a villain - though possibly an unknowing one - suggesting that he is the murderer of Tobias Grensret, or the Prophet who gives orders to the Azadi Emissary and even that he is the unseen attacker who faces the White Dragon (and therefore, presumably, the 'immortal enemy' that has been hunting the Draic Kin).However, the nature of the Undreaming is completely unknown. It does not appear at all aside from its brief appearance at the beginning of the game, and its only mention since is a sentence at the end of the credits stating simply that 'The Undreaming Is Unchained'. But if Brian is possessed by the Undreaming, it has essentially been unchained for three hundred years, and we have no evidence that it has done anything in the meantime. It might not even be a sentient creature, as it simply flows towards Brian, so to what degree it can make plans is questionable. Finally, as we do not know what the Undreaming is, we can have no idea of what it wants - only that it seemed to want Brian Westhouse, and that he was some kind of 'perfect candidate'.
An Alternative to this is that as it stated in the game, that Brian had to do something in order to get out of the timelapse. It could have been that for three centuries he was frozen in time with the Undreaming, only to merge with it just to escape the timelapse.
