Park creator Robert Ford opposed the Delos plan so programmed a complex series of events in order to thwart it, give the hosts consciousness and ultimately, free them so they can replace humans and become the next step in evolution. He also had Bernard create the Valley Beyond inside The Forge, a virtual paradise where host consciousnesses could live unbound by human-enforced narratives after their bodies died in the park.

The now-conscious Dolores, intent on defeating humans and taking over the real world for hostkind, destroyed all the hosts back-ups held in The Cradle (meaning their deaths would be permanent) and started to delete the guest data held in The Forge before Bernard killed her, preserving most of The Forge data. Realizing he could be the last of his species, Bernard decided he wanted hostkind to survive, so built a host copy of Charlotte Hale and put Dolores consciousness inside. The new Halores, despite initially rejecting the Valley Beyond as just another man-made prison, uploaded the host paradise (containing hundreds of host consciousnesses whod chosen to walk through The Door) to somewhere Delos would never find it.

Disguised as Hale, Dolores then escaped the park along with five other consciousness pearls (whose, we dont yet know). On the mainland, Dolores used the rig Ford had left for her in Arnolds mansion to build herself a new Dolores host body, and to build another copy of Arnold, despite knowing that he would attempt to stop her plan to take the world from humanity. She knew that Arnolds opposition to her plan would strengthen their species and it would ultimately be better for hostkind.

If season one was all about Dolores journey to consciousness, then season two was about her journey to empowerment. For Dolores, this began when she took on the persona of wild-west terror Wyatt, a role written for her in Fords new narrative. As Wyatt, Dolores was unyielding and vengeful, and very unlike the Sweetwater ranchers daughter we knew. Incensed by the pain her father Peter Abernathy had been put through as the delivery system for the guest data Charlotte Hale was smuggling out of the park to Delos, Dolores became more and more determined to take revenge against humanity. Gradually, she realized that Wyatt was just another role written for her, and began to act as herself. That self was bent on a desire to reach the real world she remembered being taken to in her past, and taking it for hostkind.

Recognizing that good-hearted Teddy was too weak for her plan, Dolores had her engineers change his programming to make him less caring and more hard-headed. This, along with Maeves judgement that by forcing the other hosts to follow her as a leader, positioned Dolores as a new version of Ford, a vengeful god forcing others to bend to her will and her narrative. When Teddy realized that shed changed him, he rejected her path of vengeance and war by shooting himself in the head (Whats the use of surviving if we become just as bad as them?)

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Westworld Season 2 Recap: The Door - Den of Geek UK