system
Given the following post, respond as if you're commenting on Reddit:
human
[WH40K] The Emperor knows what will happen up to 41K from the start, how does he act differently?

Basically he knows one possible future, how does he change it?
gpt
Kept a closer eye on his primarch lab perhaps? Killed Magnus outright? In truth, all the Emperor would needed to have done was not teleport to Horus' ship and things would have proceeded so very differently.