Every round you regain 1d4 hit points because of this natural regeneration.

Your body’s temperature is always the same. Because of this you are immune to being frozen or hot. You also cannot get a fever or cold.

As a dragon-kin of some sort, you can slither through the sky as well as slowly burrow into the ground. In the heat your flying speed increases by half as your body and the hot air resonate with each other.

You and your people have hunted for eons. Doing this you have adapted to have a sense of smell that gives you a second sight. Allowing you seen through fog or the dark. However not in color. This also allows you to track a scent.

Your ancestors are with you always. Because of this you not only have a spirit you can see at all times to guild you through tough situations. This spirit can pass through walls, speak to you, and empower you giving you inspiration once every long rest. After empowering you the spirit vanishes until you take a rest. 

Your spirit may break free. When you reach 0 hit points Your spirit breaks free and emerges as a Red dragon based on there age. This dragon will attack anything it sees. Though it prioritizes things it believes to be a threat to the body now laying on the ground. This is why your people were imprisoned. This dragon will go away after either you regain consciousness or you die.