Westworld: 9 Mysteries That Season 2 Must Resolve
3. Is Arnold Still Out There?
We know who Arnold is, and really, we've known for a while: Ford's partner, who created many of the hosts, and may have actually done the lion's share of the early work on the hosts. To some extent, it seems Ford himself doesn't fully understand them, though it appears that in the end, he found out how to make them become self-aware: suffering.
We also know Arnold's fate: suicide, to release the hosts from their bonds. Lets call it suicide by Delores. Arnold believed that if he were dead, the hosts couldn't be returned to their lives of slavery.
He was wrong. They were wiped, they were put back into rotation. Maybe he understood that. Likely he did, it's why he created the maze.
Yet did part of him survive? Is he somewhere in the park, living on in the consciousness of a host? It's an unanswered question, if you look past Ford's (biased) answer to the Arnold conundrum. After all, someone killed young host Ford's dog, and it wasn't Ford himself.
Who else would it be, other than Arnold sending a message?