Which stats are required for it? Is AP one of them? That's the only "stat" that isn't 1000. Can anyone confirm if that's required or if the achievement is bugged for me?

There aren't enough books on site to get AP to >1000, but now that you've mentioned it, I also have a pet that high but didn't get the achievement. I don't know if there is a page that one would need to be on to have it register? I just went to try a few links off the pet page that seemed possibly relevant but nothing triggered.

yea there aren't enough books, but in theory, with stat boosters, you could get to 1000 AP = 16k intelligence. Would take billions probably

that's true. Double checking the In-Depth Guide in the battle colliseum, it is Intel rather than AP that is listed as a stat? One of the subeta wikis does say it includes level (Which at least my pet doesn't meet, so my example is a moot point). Maybe visiting the training center, pet page, or the various links in the BC will trigger something for yours?

I want to say the way to trigger it is viewing the pets page that shows all your pets(personal tab -- pets) but its been years for me so not 100% sure anymore(I know thats where ya go for all the other stat related though)

If memory serves, there is some sort of bug and I think it actually needs to be 1,001!

Edit: Yes, train your level to 1,001 and you should get it!

Thanks that was exactly it. fyi the level (/stats) needs to be 1001 and then the pet status page will trigger it.