Hey there and thank you for the feedback on the first boss! Played With Fire is working on a first patch that will adress some of your concerns and to increase clarity on how to progress, amongst other things. In general, it helps thinking about Mixture's gameplay in the context of more traditional flatscreen action adventures where bosses will have different phases, and a timing of when they are showing their weak spots and you'll need to focus on damage.

[Spoiler] For the snake boss, you will need to throw mixtures to manage the vents (there's one in the celing as well!), where closing off the ones on the ground will trigger the one in the celing. Doing this at the correct moment will stun the Snake and you go in to a damage dealing phase, hit the weak spots! And as always, don't stand on the red stuff on the ground, dashing away to avoid being hit is key.

Hope this helps and don't hesitate to comment if you have any further questions!

For more tips and tricks, Played With Fire have a friendly Discord server here: https://discord.gg/RB8yNeexN5