I'm writing a story taking place in the semi-recent aftermath of a period of Human-Dragon warfare. The main character falls into a pit used during this period by dragons to trap/store/dump prey (humans).
For aesthetic purposes I'd like there to still be recognizable human bones, possibly still bits of flesh. My question is how long would it take for bones to become brittle, to the point they would snap when stepped on without crumbling and would there still be any flesh? Also could a snapped bone become a dagger of sorts? One time use only, just to help the MC get out of the pit. The warfare period lasted for some time (still deciding just how long), so it's likely there would be remains from a range of years.
Also for context, since I know that climate and other factors affect decomp, the environment is somewhat humid with a mild range of temperatures. The pit itself is in a forest, dug into the mud, probably largely clay in nature, and roughly 15 feet deep. Rain is not uncommon in the region, but the pit is largely sheltered from rainfall by trees. Flooding is obviously a consideration with these parameters, but whether it's the dry season or the pit is somehow protected from flooding, at the point the MC is in the pit there is no standing water.