My headcanon is that he kept memory of all those threats in case they ever needed to fight them , but he only wrote about them once he subconsciously began to change on earth.

I started the comic a couple weeks back and I’m almost done with it, but there’s a lot of events I feel get skipped or just glossed over and you just learn about them from a panel.

The show did a really nice thing to show Nolan’s journey outside of Earth after the fight with Mark.