I found a few so far, but I'm wondering if there's any more:
Polychrome: https://itch.io/jam/gmtk-2019/rate/463520
Chamo: https://itch.io/jam/gmtk-2019/rate/462846
My game, Minute Escape: https://itch.io/jam/gmtk-2019/rate/462374
There are no upgrades, but it's got exploration + platforming mechanics, maybe it's a close enough fit for you https://itch.io/jam/gmtk-2019/rate/462355
It's like a brainvania! You don't get upgrades, but you learn new things that you're allowed to do that you didn't know before.
