Shroombo

 "A mushroom sprite who resides in the Spirit Tree. With its bright red cap and stocky build, it's very much a mushroom indeed. Although it seems to have also sprouted legs somehow."

Shroomba is a playable 1 star, Fire Bruiser. Shroomba can only be found only by finding and tapping its sprite in the town square of Stardew Village.

It is listed as a Springy Spore Sprite in its description.

It starts out at a level 40 cap, that can be increased by either finding duplicates or with the use of 3 star Astral Gems. (4 star gems may be used, but should not be used for this purpose)