This game looks super good and is presented super well considering Pico8's limitations. It is very polished and doesn't seem rushed at all. I do wish there was a little more in terms of content though. Maybe a shop to upgrade skills or items?

The game is very simple, can you add more types of bubbles? My, score: 9590

Dude this game is cool. I went for the pacifist play through, haha jk I was nervous to shoot because it costs O2. Anyways it was fun lol. The sprites look great and I like that you used a specific selection of the already limited Pico-8 palette. Killer.

The concept and use of the limitation are very clever and for the most part it works how you intended it to. I think shooting the poison should destroy it first shot every time that would add more balance to the gameplay. Presentation is excellent -- I love the music!

The concept is really neat, the idea is great, but evading the enemies as a whole is just much easier and better for recourse management than attacking..

The art style is brilliant, along with the music! As a whole, the game looks and sounds really nice. Only small complaint I have with the presentation is that the background made it a little difficult to concentrate. Making the stuff in the back slightly darker or such would help with that.

Plus, not to forget the achievements! Really good addition. Honestly just a really cool game overall.

Pros:

1.  Achievements. Come on, guys. Where did you find time for this on 72 hour jam?
2. Cool cheaptune

Cons:

1.  Background musics restarts when you are re-entering main menu, from credits for example. Sounds clumpsy.
2.  Enemy looks like a bonus. Try to add some spikes on it.
3. Top bar is just a bar. Change it to health/oxygen bar. So it will be easier to track your status.
4. Static difficulty. Get booring very fast (At ~5000 score). Increase the speed/enemy amount each 1000 score.
5.  Firing is overrated, only evading is enought. Try to add more targets for my bullets. :)