Is it correct to say "imperturbably take damage"?

I have the next sentence:

Stay calm and imperturbably take damage or die if need be.

Is it right? Can you give me any suggestions?


Original: “imperturbably take damage”

Its sounds very odd to me. "Unflinchingly" (without moving) would sound better.

"Imperturbably" to me implies mental calm, focus, concentration. Taking damage to your body would perturb your mental state, I would think, unless you are a 12th Level Buddhist master, or your limbs are paralyzed and can't feel pain.