Hey, I just finished playing your game. It was lot harder than I expected. Like... A LOT. Before I get into my feedback I think I should say that there is a lot of potential here if you can make something like this being brand new to game making in general. The game is far from perfect but if you keep at it I can see you making some great things in the future.
Now let me start off with the difficulty, which is the game's biggest problem in my eyes. Around the last screen of the third stage there seems to be a massive spike up in difficulty where the gimmicks are starting to be crammed together into very awkward sections. Before that point I was making progress at a quick pace but one I got into stage 4 it was very slow. The only break was area 6 which was pure needle and I felt was much easier than the previous three. The reason why this difficulty is a problem is because your gimmicks are all timing based. When I was playing this game I kept wishing the rooms were less tightly packed and much easier and then maybe I would enjoy the gimmicks more. There are some really neat ideas in here with the gimmicks but they are undermined by the sheer difficulty and tediousness of the segments. Also, when you are working with timing based gimmicks you really need to be careful about how long the player has to wait upon restarting. I found myself having to wait up to two whole seconds at the start of every attempt on some saves just waiting for the cycle I wanted. This is something you need to avoid or else the player will get impatient very quick and end up with a bad mood and probably quitting.
The next issue that needs to be addressed in this game is the visuals. I'll go through each stage and explain what I like and dislike about the visuals.
The first stage is easy on the eyes but I found the tileset to be very odd. Why am I jumping on the sky surrounding a flower? It feels like the flowers should be background objects to compliment the tileset but you used them as blocks instead. It's not terrible looking but it looked very confusing to me.
I wasn't a big fan of the second stage's graphics because the blocks hurt my eyes. They are too bright. I would make them scroll slower and also be less white. The spikes are okay.
Stage 3 = seizures. I actually like the animation on the spikes a lot and the background is okay but maybe a bit too fast scrolling. The blocks are super distracting and I would probably remove the animation on them. Be very careful when implementing animated blocks. It's a common misconception that the more animated objects on the screen, the higher the production value. I learned quickly though that doing this can make your screen look too busy and hard to play without straining your eyes.
The fourth stage would be fine with a background added, preferably something simple. It was honestly a huge relief to get here after staring at the third stage for almost 20 minutes.
The fifth stage was back to hurting my eyes. I really dislike pulsating spikes, especially if they are all doing it at the same time. The foreground objects are just too bright and flashy and that combined with the awful dubstep music actually gave me a headache. (This may be more of a personal problem but I cannot stand listening to dubstep music, especially if it has a lot of wubs). Anyway, I would probably fix this by making everything a light gray instead of white and also making the spikes less red when they pulsate. Also make them start at a random pulsation value so they are not all flashing at once. (Trust me, this helps).
The sixth stage was fine, I had no problems with it.
And the last screen... I think you know already. It's a goddamn nightmare. Granted, it is funny when you first get in there but after a while it becomes torture to look at.
Finally i'll talk a little bit about the level design in this game and how to improve it. I already said how the difficulty needs to be toned down a lot, but you also need to think about variety in the platforming. I saw a loooooot of diagonals, gates and corner jumps around this game and I think they are really unnecessary because you have gimmicks you can use in much more interesting ways and these generic needle jumps are just breaking the flow. I think I should point out that the last save in the game is literally just four corner jumps in a row. There weren't too many corridor designed rooms though, which I was impressed by, because that is a design trap that a lot of new makers fall into.
This is just a minor nitpick, but I would prefer to have sound effects when things appear / disappear in the game. Maybe you removed the megaman block sound because it was annoying, idk. It's just weird to have blocks suddenly appear next to me with no sound effect accompanying them.
I think that about covers my thoughts towards this game. It took a lot out of me to actually beat this game but I definitely didn't hate it. And I think if you keep making fangames and putting effort into making them fun and interesting you will end up making something great. Sorry for the long post