At the the sound of the deafening noise, K'eth just stops, eyes wildly starting to focus and move to pinpricks in splitseconds over and over.
Then... he starts to laugh, and it isn't in his normal voice that he laughs, it's way more... child-like, and almost repeated as a wordless mantra, over and over again. His eyes still forcefully shrinking and enlarging in pain.
Pain, pain, pain, pain, pain.
K'eth's emotionless expression gives way to sudden voracious rage, and Themadon sees lines forming on K'eth's lower jaw... wait what? This is his weakness, he shouldn't be able to-
CRACK, CRACK.
The humanoid's lower jaw elongates and breaks out into two fanged almost insectoid segmented limbs, chittering gutturally. His neck rips open, revealing bone after sharpened bone. Gnashing at nothing but of the prospect of flesh in it. A sickening sound of twisting flesh comes out over the cacophony as K'eth's exposed belly rips itself apart as eight rib-like teeth twitch and flail around along with a thick meaty unnaturally formed tentacle that flails as well with it's 'teeth.'
Even with all of this happening, more changes. K'eth's back starts to rise up in contorted skin and then breaks apart suddenly and viciously. Two wings now sprout from his back... but there is no flesh to their name, only a faint reminiscence of draconic pride.
'K'eth' Gets on all fours, roaring out a mindless challenge of hatred and ferocity... and charges at Themadon. Phase 2 of the boss fight starting.
(Sound makes it so he cannot do further 'modifications' in the world. It doesn't mean he can't have a backup for when it DOES happen... and it is happening. Also, since I said it... Boss music! https://www.youtube.com/watch?v=lIjcCzNu8PM )
Imbellis blushes and nods to herself. "I... like you both equally, as you are both the s-same person... It is only natural, right?" The fog crawler fidgets around at revealing such a thing. "I apologize if... you w-weren't ready for such a thing."