Very cool little puzzle game !
I liked a lot the concept of sacrifice, and the way you made the player understand the new mechanics by visual and interraction (the first level you discover the breaking plateform your first move shows what it's doing)
The fact that there was a target to achieve made so that it was possible to only seek the shortest path that took the souls to their position and see if it validates the target, so it can change the focus of the puzzle to optimisation, but even with that you have to show to the game that you understood its mechanics to proceed forward
The game is very nice to look at, with a lot of polish on the animations and the experience !