Not this again (On Break)

I am making my morning rounds when I come across Jason's empty cell. I stop myself from calling for help, and begin to investigate. The cell door is firmly planted into the wall across from its original position. I proceed over to the door looking to see how it was possibly removed.
I begin by searching for a burn mark from a lightning bolt. I find nothing. Then I start to feel for any abnormalities in the bronze. Rubbing three fingers slowly over the door. As I'm about to give up, I feel a small dent near the feeding window. Leaning in to get a better look it appears to be an indent the size of a fist.
This resolution puzzles even me. How could a mere demigod break a cell made of pure celestial bronze?
I finally leave to find some evidence of where Jason May have gone. I proceed out the door still scratching my head.

Notes

Sorry this is such a short chapter. Remember to check out the story I'm co-writing with @seaweedbrainxxxwisegirl. "Harry Potter games and may the gods be in your favor" is a collaboration of a lot of different books (and animes on my part)
Thanks got reading.