How do pets level up? Is it determined by xp you gain, or by their actions (healing/gold find/item improve)? My Imp has been level 87 for a couple hundred floors, and while I’ve been getting the stat buffs from every 5 rescued enslaved pets, no level increase, so I was wondering how that worked.
Pet level up just like you leveling up your character, but it takes a little longer. Try adding some MS with % exp gain, it’ll help 
nekobawt,
Hi, I have some advice for your pet levelling.
Try levelling at level 191 - 200.
I had a pet at lvl 93 who did not level up even after 30 odd maps at 350ish. I carefully watched the experience bar and it was going up marginally.
Upon going to 191 and completing the level, the experience jumped noticeable, (roughly the width of a letter of the pet ability).
If it doesn’t increase noticeable, select the same level, upon starting the level it should jump up right away. Perhaps there is a cap upon pet exp per level?
Any way give it a go.
Secondly regarding the pet abilities, I levelled from 93 to 97 and did not have a single ability increase!
I thought it might have glitched, so I equipped a level 20 blue pet, levelled it a few levels and re-equipped the lvl 97 pet.
At that point the pets abilities started improving again, both from levelling and the feat.
So thats another thing to try.
Good luck!
When your pet level up, he has a small chance to increase his stats. So it’s normal if his stats stay the same 
I have 3 level 99 legendary pets. They aren’t hard to level if you know what your doing. I’m ranked 29th for highest XP gained.
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