Help with a certain boss

Hey all! First of all, I wanna say that the game is amazing in its current state and I cannot wait to see what the final product looks like.

Secondly, and the main reason for this post, the fight with the second boss (a certain flying creature) of the surface path of the game has me raging. I cannot find a way to beat her for the life me. I just had an attempt in which I had five death defiances, a full health bar and decent dps, but still I couldn’t get past her.

Please recommend me some tips so that I can finally put her in her place.

Thanks in advance!