- Serac believed it to be Maeve - not Dolores - who beamed The Valley Beyond (with all the hosts uploaded inside) to the secret coordinates in the season two finale. Because Maeve had the most motivation - to get her daughter to safety - and because she displayed special powers before she died, Serac believed it was Maeve who not only knew the coordinates, but was somehow causing the divergences that Rehoboam is detecting. In Matrix terms, Serac essentially believed Maeve to be "the one." Via Rehoboam's vast and complex algorithms, Serac can basically see the future, and Rehoboam is "telling" him that if the divergences continue - and presumably if The Valley Beyond is not found - it ultimately leads to the end of mankind.
- So Serac presumably sent someone to Westworld to retrieve Maeve's brain pearl from her dead/decommissioned body (remember, she "died" at the end of season two). Now with her brain pearl in his position, Serac then created a simulation (War World + Simon) to try and trick Maeve into revealing the coordinates of The Valley Beyond.
- The first go-around of the simulation, Maeve believes it to be real and that she has been recommissioned in a still-in-operation part of Westworld. She's still the same Maeve from the end of season two, with the same memories. Only her "powers" no longer work. She realizes something is truly wrong, however, when Hector calls her "Isabella" and not Maeve. So, after killing herself in War World, Maeve wakes up in the lab, still thinking everything is real, and tries to kill herself for good with the nose thing. She saved her daughter, and she's not going to be a puppet anymore. That's when Simon shows up. Simon then places Maeve in War World once again, this time with a plan hatched between the two of them for her to join her daughter in The Valley Beyond. It's on this second go-around, however, when they're in The Forge, that Maeve realizes this isn't the real park at all - it's a digital simulation. So she and Simon go back to the lab, and this time, it's Maeve's plan that they both follow. She wakes up a third time in the War World simulation, now knowing it's a simulation, with the goal of crashing/freezing the system. The freeze then allows her the time to hack the real-world the facility in which her brain pearl is being housed, she hacks a worker robot in said facility, and unsuccessfully tries to escape with her brain pearl.
- Upon realizing that Maeve is not "the one"/didn't know the coordinates, Serac comes to the conclusion that it was Dolores - not Maeve - who beamed The Valley Beyond to the secret coordinates, and that it is Dolores who is causing the divergences. However, during the simulation, Maeve still proved her mettle, so to speak, so Serac decides to create a new, real-world body for Maeve, and puts her brain pearl inside (with all of her memories intact), with the goal of using Maeve to now track down and kill Dolores.
