This is a really fun game except for some minor bugs. I think you can slide through the levels pretty easily if you press W and D at the same time when you're resting at the idol. But it's a really interesting concept with the sonar and I got really nostalgic with the game Badland.

Cool game! The idea of invisible level is great! Maybe the flight mechanic could have been smoother, also I found a bug where you can move without flying when you respawn sometimes, but except these small things it's really good!

Ooooh I love the concept of the echolocation, it was really clever to have it bounce around like that. I think you could take this even further and leave fading marks where the geometry is and give the bat much less vision, kind of like those LIDAR-ish games where you gradually build up an image of the environment by scanning. Well done, this was inspiring!

Flappy bat! A very cool mechanic, and I like the simple yet polished gameplay.

Very often (after restarting or when stopping in a nest) I triggered a bug where you could slide around the ceiling with the left/right keys without having to fly. It was a fun way to cheese some levels :-p

Loved the sounds and the music! And the graphics are nice! The player controls are quite difficult though, especially since you need to use the mouse while keeping the space bar pumping..