A solid game! Enjoyed playing it.

Loved the Metroidvania vibes and the art style overall (it's fantastic!), caught one text "bug" it is attached to this message. 
The jumping works but a little bit unresponsive but I know that you probably spent most of the time on the levels and it was the right decision. One problem I got is the respawn on a golden key system it would be more pleasing if there were some different checkpoint system at the place (I am terrible at any platformer so going from the key every time I died at the pit was not so great).

You made a cool game with a lot of potential. Here are some thoughts and annoying suggestions:

- The attack button was in a bad place, it would be better if it was the left mouse button.
- It was annoying that I had to kill all the enemys to be able to get into the next room. They should be there, but it would be nice if I had to choice to kill them or not to. Also they didn't looked like enemys should (e.g big ,dark,bloody, something you would find underground and would want to kill you).

I loved the art and the music, everything worked really well together making a relaxing/sometimes frustrating experience. If the post-jam version will ever come out, please message me. :)

Very good graphics and sound, I got stuck after getting the double jump ability my player disappeared completely. Not sure what you sacrifice here doesnt really fit the theme.

Cool music and art!

I love the artstyle and had realy fun playing your game.

Doesn't really open properly, tried windowed/fullscreen mode and the game plays audio but the window auto hides? Using Windows 8.1

Really nice game, hope you get good ratings!

I think this game is more suitable for mobile phone platform

Very pretty game, I liked the music too and it was fun to play!

A few things could've been explained better: the fact that to go down you need to press down + jump, and the fact that all the enemies need to be killed in order to open the doors (I was blocked in a level and I thought it was a bug :P).

Also, I felt like there wasn't much of a "sacrifice" to make, since we never really had a choice not to take the power-up, and we didn't know what the effect would be beforehand.

I really loved this game. I found the music and mood excellent. I would have like it to be longer :) Thank you

This is a really neat game! I love the art style, so cute! The music is great and the level design cool!

I really liked the art! It's very beautiful and I like that the different rooms have different coloured platforms so I actually know which room I have entered before and when I see a new colour I know I have to explore that. It's a very nice touch to help the game be more navigatable.

The appearance of traps when I picked up one of the upgrades is a really nice environment change that actually adds more depth and challenge to the game. I didn't complete the game due to reasons below but I hope there are more of these down the line rather than just increasing enemy speed which does not necessarily make the game more engaging or interesting.

I think the deaths get way too punishing. After picking up the upgrade that spawned the traps, the same room also had a very low ceiling. Combine the low ceiling height with how high the character's jump height is, it makes it very easy to fall into the traps in this room and the ones after as I always hit the ceiling and fall into the traps. And when I die, I get sent back 3 whole rooms! This made the experience slightly repetitive and possibly maybe too difficult. However, it just might be that I have not mastered the controls so you would have to check with other playtesters too.

I personally feel it was more of a game where you get benefits but the benefits come with a catch, which makes you disadvantaged, and not necessarily to do with the idea of sacrifice, but that's alright to me as it still makes for an interesting game concept.

I liked that the glow was used to bring attention to the traps, and also I loved the death animations/FX left behind by killed enemies. With the music, it sets a unique mood for this game, so good job on that! Keep it up :)

I really liked the artstyle and the audio of the game. You guys did a really, really good job there. The idea of the game was great too, although it didn't give that feel of sacrifice. Also I'd wished the smoke effect when the enemy slug things die wouldn't move.
But I really enjoyed the game. Great art, great audio and good job. 5 stars on audio.

Nice game!

People have left a few thoughts and so I'll just add a small amount of random feedback:
- I wish I could move faster
- In some ways the game world felt a little 'empty' (which is totally understandable given it's a jam game haha).
- Those jumps where you have to jump a small height were super hard haha

Great mood! Very nice use of bloom to make certain elements like the traps visually pop. I also like the very smooth camera movement between rooms. My one frustration was the range of the attack; it was quite hard to hit an enemy even when it was right in my face. But overall, excellent!

Nice pixel art and visual effects! It's impressive how you made a game with character progression all alone in such a short amount of time.

Checkpoint placement is pretty good, thank you for that!

At the same time, I must say that this didn't really feel all that much like a metroidvania since I only ever got one fairly standard new ability: the double jump. And when I got the double jump, there wasn't even a notable trade-off so it felt kind of off with the theme.

Generally the sacrifices felt more like trade-offs than like sacrifices. You could say, you sacrifice easier combat for an additional heart but that seems like a stretch, haha.

It was still very enjoyable to play and I had fun exploring. I liked how the level changed when the traps were added. Made backtracking way more fun due to the added challenge. Good work!

I finally finished it this time... My previous play I died a lot by touching spikes.

Nice game, and I think everyone else said it already.

I must say I like those moving smokes, so you don't need to change them for me.