It's risky but I had a used Zartan I dipped in boiling water, which made cutting him apart easier. But the hard plastic can warp out of shape and has no "memory", that's the risky part. I know I ruined a used Serpentor with a stripped screw...oddly the screw fell out, but I left the torso in too long...warped beyond usage and discolored strangely.

So, not recommended. But I mentioned it anyway.