Thank you for sharing this quite unique puzzler, my mind is dancing inside with the way it all works.
I love the initial animation with a grid of square animals, and round animals on top of that. Looks like a nice lock screen / stare into space screen.
initial loading screen : it took quite a while for the initial loading, maybe a minute. While the square animals in the background and round animals floating above were fun, I had a hard time waiting so long. a progress bar, or mini game would be nice.
Level 1 and 2 : nice flow, clear what to do. the little hand made it easy. at first I made them walk past each other, then I saw that I am controlling both, and they need to go together.
Level 4 is hard : after the initial levels that were so easy I was surprised at how challenging level 4 was. There is some magic on that level which needs a bit of a demo. Level 5 has much hand holding, the square dog is up above, the playing field is made more narrow, and there is a hand showing me what to do. Compare this to level 4 where the big item of interest is the change in speed depending on what color ground you are standing on. And on level 4 there is a wide open field where I can get lost and make many mistakes. Probably you want to limit what I can do on level 4.
Going back, I see that level 3 was the explanation needed for level 4. However the secret is shared in small text, I tend to ignore the small text. In fact, I would suggest removing all text from your screens, and stick to symbols. for level 3 I'd go with a closely dashed line on the right, suggesting slow movement, with far dashed lines on the left, suggesting fast movement. - - - - - - - - - - - -
I would add another lesson level between levels 3 and 4. have level 3.5 be similar to 3, but have more steps going left and right. Level 3 has a single step, go left, then go up. This is too short, not enough interactions to grasp that there is a speed change going on. Have me go fast left, then go up, and go slow right, then go up and go fast left again, then go up, then go slow right again, then go up and win. by showing the difference in speed a few times . . . well, you know.
Also, considering that level 4 is the first time focusing on the speed difference, I'd remove the lower grass, and only have the border above, maybe put in a fence like you have in level 5.
transition between fast and slow : If I move up and down, into and out of the grass many times, I gradually move down relative to the other guy. the transition into speed happens more quickly than the transition to slow speed. this means I cannot go backward in progression, I cannot work back to where I was. my expectation is I can reverse my steps and go back where I was, but my experience is that repeating the same sequence of going up and down, where the fast guy is going in and out of grass, causes them to slowly drift apart. By only having grass above it removes the wrong path of having the fast guy use the lower grass.
nice arc symbol : Level 6 has the little clue of a blue arc, showing how something will rotate, I really liked that, gave me something to watch for. Give a symbol showing what lesson I am learning, what I need to watch for. Your cool game has so much going on, so much to discover and try out, the symbol helped me focus.
reset button : for me the traditional symbol for the retry button is a semi circle arrow. an arrow pointing left to a line suggests rewinding, or going back a step.
I like the colors, made it feel fun.
level progression felt good. I made it to level . . . hmmm, hard to tell what level I'm on. I tried many, ah, finally I see : Level 12
font : you cannot skip levels. reads like : you cannot ship levels. the H and K look quite similar.
intro movie : I'd like a way to play it again.
I'd like more easy levels with different animals in different layouts. Hard levels are fun to solve, but there are times I'd rather have a variety of easy levels to casually do one after the other.
thank you for sharing the game, I enjoyed it, quite fun and engaging. when the level got tricky at 12 I started to lose interest, I'd rather just move things around and watch them pair up.
freedom to move all around, and progress of learning and getting better = good motivation