Really creative little stealth puzzler! The echo mechanic used to scout the floor below is such an interesting mechanic!
I really appreciate being given as much time as I needed to scout the floor below before committing to drilling down to the next floor. Alternating between the planning stage and action stage feels like such a natural way to mix up the games pacing given the theme.
It might just be me, but I sometimes found myself bumping into and getting stuck on walls in the current room when they were hidden by the echo projection of the room below. The only improvement I’d suggest would be to consider hiding the echo projection of the room below as soon as the player starts to move.
That aside, the procedural levels are a great touch, and really well implemented at that! It really helps to keep each level feel like a brand-new puzzle when revisiting the game.
Overall, very impressed with this one! Interesting idea and well executed! Looking forward to seeing what you make next!