Idea: Chase’s Injuries
Given that it could be seen that the energy blasts that Caleb and Chase were throwing at each other were more like a solid, than It can be assumed that when Caleb was given his father's powers at the end and managed to win the fight ultimately by sending Chase's own energy ball ( super powered up ) back at him, and through him. Chase would logically have been critically damaged due to something like this. My assumption is that major internal organs in that area and interconnecting areas were in some way damaged, as well as bones, including his rib cage and spine. His spine could have been severed, and his rib cage crushed. Picture a boulder that size being thrown into your body. If you were to survive the impact, if it were possible, you would be left with a lot of damage.
But that being said, Chase was not only hit by this energy had it go through a body, he was tossed into a fire, and potentially swallowed up by a portal to what could be assumed hell/another dimension. What happened to him inside Hell or whatever dimension, who in the hell knows. But let's just say that he could have also teleported out of the fire and to safety. Where he was taken to a hospital and left in a coma as he healed from his burns and torso injuries. Though upon waking up Chase found he couldn't move because he had been paralyzed from the energy ball attack. Which he would obviously not be able to deal with and probably would want to die. But instead, he spent all his time finding a way to fix his spine. Eventually using The Power as amend between the break in his spine ( Don't ask) which serves now as a way for him to both use his powers endlessly and prevent me from having to showcase that he wants to use constantly, because he is constantly using by using The Power to be able to walk again. He also uses The Power to stop the pain from his burns, and his internal injuries.