Yes there are 2 more bosses for you to find: the swamp slime queen, and the blue vixen in the high-tech area.
Oh right, those new areas and bosses exist only in the up-to-date version released on my patreon.
This here free version is a very outdated one.
When I finish the development of the game (getting close to it!) then I'll release the full game here as well, but for now I'm doing sort of a closed-beta, releasing new updates exclusively on my patreon page.