9-10 final boss pure achievement glitch? Help? RESOLVED:IM DUMB

[Jing Dongle]

I restarted this game on the steampunk world so I could qualify for the "pure" achievment.
Unfortunately, on the final level of 'hell'. 9-10, About 8 or 9 times now, I sprint up his damn arm and jump on the green button. The second I touch the button, Im launched in the air maybe 10 feet. then die from an explosion. I've watched videos of the boss and he seems to die the second people hit the button. I've beaten him atleast 8 ♥♥♥♥ing times. Im startting to lose my mind.

Making an edit because steam guard is trash.



EDIT:

Okay! im an idiot. Thanks MM4005 for holding my hand through this tragic experience

[Hddn]

You gotta do all levels without abilities not just the boss

[Matt]

You have to press the green button 2 times. After the first time you have to jump back down to the bottom.