This game is absolutely delicious. Feels (at least to me) very much like Link's Awakening or other Zelda games and I loved both those and this. I found it super charming and it totally doesn't overstay its welcome.
I have two main criticisms:

1. All the upgrades / weapons (besides the sprint) do the exact same thing, which is fighting enemies and destroying barriers / plants. The only difference being the durability of the barrier you are able to destroy. And I would say the axe completely trumps the sword for being safer and able to hit way more things at once. I think it even beats the claymore (which oddly I got after the AMVE).

and 2. The enemies go from "complete pushover" to "will two-shot you" with no in-between. I made a mistake like this in my game (even worse so), so I relate a little and get how tricky enemy balancing is, though. Although, at the same time, maybe this is a way of expressing how dangerous the cave area is? Idk. I personally found it a bit jarring but it wasn't too bad after a couple of attempts getting used to it.

Overall this is a really great entry. Easter eggs are fun, the atmosphere is good. I hope you keep making awesome games!

YOU COOKED HERE 10/10 

Damn at first i felt a bit weird out cause beeping stuff but thankfully the beeping was soft and gbc style which i am cool with then i was again scared for a sec when i saw its top down and has combat but was happy to see some really good combat when i mean good i mean amazing its smoothness and snappyness shocked me and the fact that there are 2 types of weapons also helped a lot i would say if it had like only sword i would have been a bit sad cause its not my fav (even the clay one) but the AXE ya thats peak honestly i am so inspired by it that i want to make a game which has that attack now literally i am not joking 

Now lets get on world design first its tooooooooooooooooo small :( (Its actually pretty big but like i want to play more )  also great secrets i did find them all but like lil swag couldnt understand the reference which i think is fine. Other than that ig the world was richly detailed like each room had something in it which is something i think lots of mvm games forget to do and instead leave empty rooms which leads to the world feeling empty and i would say the metroidvania part is a bit weak like i would have appreciated there being a secret somewhere in the bottom right iesh part so the player has to revist or come back later or never find it on their 1st playthrough it would have made the experience so much more richer i would say either way i found the world not that hard to navigate in but it was fun to travel in it and never felt lost (Which is good)and personally enjoyed some of the secret finding also i would say i found it all by myself but i did ask a hint once so :(( 

Now music its not my fav to hear beeps but like i send this game gets a pass cause its a bit soft also like the sensory is only where i took a star cause the music also my fav track probably is the start one its so pokemon and gbc like i loved it and ofc while we at it the dramatic effect at the start was amazing the no music before sword and then boom music I LOVED IT that was beautiful other than that i felt like the secret black area music was a bit meh but its only 1 rooms so its not that bad 

Now Bossfight , ONLY 1 :((( i was sad cause really like the combat once you get used to it its so satisfying but the boss its self i would was a bit too cramped i would say and possibly hard (which i dont hate) but the bullets stacking at times made the fight towards the end a bit rng heavy i would say like if it pick the below line and the bullets are going up and you are on 1st line then you are good but if you are one the 2nd line then basically its a hit for sure which feels bad , i would suggest making it so that there is no side attack cause the fight is pretty hard and fun as is so that not being there wouldnt change that i think and would make the fight less rng i think rest of the fight was actually fun i enjoyed learning its patterns and the end phase is hard to understand i would say but like you did tell me on discord that you wanted to do something else but time so i hope its better in a future update if not atleast make do that when it has 3 bars left and let the player damage it during that time 

Now Iframes this one i would say was something i found thats weak in this game especially player Iframes they stun the player and dont allow for movement which makes its possible for the enemy to continue to attack which leads to getting hit before you get control back.The enemy Iframes are actually pretty good i would say maybe reduce their time but its not needed 

Now Reference inTerms of MVM, AMVE was a great idea and i liked your way of thinking too actually its a very well implemented  and the kei being the name is very intentional and appreciated i would say 

Finally polish , this is one thing thats done a lot in the game its small but its super polish and has great effects and stuff i would say 

And this is Pretty much all i wanted to say and one final thing i wanted to say was which i hated the most about the game is ...... winterbraid should have worked on this since day 1 so i could play more i really need more pls make more. Also thanks for reading till here you actually rocked and i think this game amazing and might be the best game in the jam and GL on future projects