Nice game, but very difficult. Big plus for Linux version, though the menu was only 1/4 of the screen in the bottom left corner. I could still get into the game, but the terminal showed a number of collision errors such as:
ERROR: body_set_shape_as_one_way_collision: Condition "body->get_space() && flushing_queries" is true.
At: servers/physics_2d/physics_2d_server_sw.cpp:739.
Following the theme and easy to pickup, good job!