Story Codex (Unlocked In-Game) Edit
As a bearer of the Crest. Sienna has been given the task of "purifying" Rieubane by the "Mother of All Things."
The Mother of All Things is the keeper of the "Cycle." She is the "will" that monitors all activity in the world.
The Crest is a sign that a person was chosen by the Mother of All Things. The Crest is also known as a sign that one can use special powers in order to perform purification.
The activation of the Power of the Crest differs from person to person. Sienna was awakened to her powers when she attempted to rescue her son Trandin who was trapped in the "Land of All Ends." an enclosed space created by Morpheus.
At that time she was also awakened as "Krisalis," obeying the will of the Mother of All Things to cut off Rieubane from the rest of the world for purposes of purification.
Thus, Rieubane became the "Lost Empire"
Even though Sienna had successfully cut off Rieubane from the world, she was unable to purify it.
The purification of Rieubane means that her son Trandin must be purified and purged, as well. She feels guilty of leaving her own son in such an environment where happiness was a distant dream, and this causes her to resist the will of the Mother of All Things.
That involves Darius.
By bringing Darius, who also bears the Crest, to Rieubane, she uses him as a diversion for Morpheus and the Mother of All Things in order to rescue Trandin.
However, her plans are interrupted when she tried to rescue Sharline from the evil grip of Morpheus.
Sienna is able to escape from Morpheus with the help of Sharline, but she won't be able to escape the will of the Mother of All Things for very long.
As her consciousness is taken by the Mother of All Things, she uses the last of her power to bring Darius into this world.
When Darius arrives in this world. Sienna becomes Krisalis. She becomes a somewhat incomplete entity because there is little of Sienna left in it's consciousness but at the same time it does not obey the will of the Mother of All Things.
The only will that Krisalis has is to lead Darius to Morpheus. This is the only objective in Krisalis's mind.
From time to time, the will of the Mother of All Things weakens, allowing Krisalis's consciousness to return to that of Sienna for a short period, but she is unable to tell Darius the truth.
It is apparent that Sienna has involved Darius in all this for her own selfish reasons. She's extremely afraid of not being able to receive Darius's help if she tells him the truth.
However, the existence of a young girl named Sharline created a small resonance in the relationship between Sienna and Darius.
Darius has a reason to fight.
Even if Sienna were to tell Darius the truth, he still would have no choice but to assist her.
But she cannot tell him the truth.
She is afraid that Darius would blame on her, pointing out to her that she is controlled by Destiny as a mere pawn, as a bearer of the cursed mark, Crest.
Darius himself has the Crest, though,
As Sienna encounters the strength of Darius's will, she comments, "You're a very strong person." She is perhaps envious of Darius's strength. But this is all a misunderstanding, and Sienna simply feels that way because of the way she is.
She is ultimately controlled in mind and body by the Crest. The words she has given to Darius would perhaps describe herself:
"When Struggling, a Crest-bearer makes currents in the flow."