Mini-metroidvanias like this are so fun to play! You picked a great mixture of abilities that are all unique and enjoyable to use. Using Big Mode to stomp enemies is really satisfying in particular, and the dunkey crab-kick is perfect. 

The little touches go a long way, like the animated background, unique normal/big/dunkey/rocket animations, the enemy sprites that change as they take more damage, and the cool hand-animated smoke effect while you're transforming. Also I can't get enough of that falling animation with the flailing feet, haha. Very well done!

The game is a nice metroidvania, although I feel like some of the powerups felt obsolete (mainly because you can push any block with big mode and destroy all the brown ones). 
I could not finish the game without the bigmode infinite jumping, because even in small mode I could not reach the platform that leads you to rocket mode (I also couldn't figure out a different way of getting up there or through the spike pit). Also very often when I was trying to crush enemies with big mode I would get hurt pretty often, which made me want to avoid enemies all together with small mode. I like that each powerup has an immediate use for them when you obtain them. As others pointed out, the lack of music and soundeffects does take a bit away from the experience. I think all together you made a good game and I think with a bit more development time you would make it a great one!

Cute little Kirby metroidvania. I think the big mode probably should have some sort of limitation on the total number of midair jumps, since you can pretty much bypass all the obstacles with the unlimited aerial jumps as it is now. Nice animations to switch modes, and the presentation is very nice.

The start of this game is really cool! You start falling down, seeing some of the level and just when you land you get told what the controls are.

Lack of audio really hurts this game, mostly because of sound effects. The enemies in this game are really cool designed art and behaviour wise, but I didn't think they were enemies at first. I didn't notice getting hurt, but eventually I figured it out.

I found it hard to kill enemies in big mode because the jump is so low. Also I didn't notice I had to hit the enemies multiple times. (This is visualised in them getting a bit redder, but I didn't see this at the beginning). I eventually came to the strategy of going normal mode to jump and land on the in bigmode, which worked.

The powerup animation is SO COOL. It feels really professionally made. I never got tired of transforming, really great job on that. 

Figuring out where to go was hard at the start, but once I unlocked the small mode everything fell into place.

Xylophone was a really funny addition. This also made me notice that every mode is activated by the first letter of their name, which I thought was really funny. It helped me remember how to transform into them.

Permadeath hurts this game a lot. I died once somewhere after unlocking the xylophone and it was a bit of a drag to go all the way back. 

The donkey powerup is really fun and so well made. Animation looks really good!

I eventually made my way to the top right, where I could see arrows pointing to my entrance (which is probably my exit). I just couldn't reach this part, probably because I was missing a specific mode. I couldn't figure out the puzzle at the topleft with the big spike gap and eventually died. 

I feel really bad not finishing this game, because the anticipation to every new powerup is just so high. The game is a bit hard with especially tight jumps for the small mode sections. You really have to power through some sections.

I did really like the game. That metroidvania feel of going left and right with your new powers is always satisfying. The art is also amazing. Really sad there is no music or sfx, thats the biggest part I'm missing here.