Originally posted by Kris Blazehe already does absorb it, it's his only means of sustenance being that his digestive organs are mostly gone or just vestigial.
then he would have been able to develop some sort of yellow-sun absorption stuff or the like.
and yeah, he can only adapt to physical attacks (hence the slow loss of organs within him (you can't train/toughen organs)), the bone armour is pretty much the best his dna can come up with.