Ghouls have seen a lot and been through a lot of slander and racism. Because of this they have mainly been secluded; either that or protesting, thus getting a different outlook on life than humans. 

Because of how immensely powerful the heatwave and initial blast were, many humans who were not sheltered died off. However, some with much higher constitution survived. Because they survived this, their body is incredibly used to enduring incredibly high amounts of radiation at once, thus rendering all ghouls completely immune to radiation. This is very useful, as they can eat any food they find, drink any water they find, and explore any radiation-infested area.

The initial blast caused a severe, inhuman amount of adrenaline in nearly everyone it affected, thus, those who survived it and were there to see it are used to adrenaline. So used to it, in fact, that they can manipulate it twice per short rest. An adrenaline pounce is when the ghoul uses an unarmed melee attack, and 1d6 is added to it. It has to be an attack such as a headbutt, tackle, or a ravage attempt; anything that requires more than one body part. 

The initial blast has caused many diseases, some useful, some useless and awful. Claws and unclippable nails are one of them. The fingernails and toenails of the human have actually absorbed toxic waste in the blast due to how vulnerable the amount of heat made them, thus, an unarmed attack does an additional 1d4 radiation and 1d4 piercing damage -- only if they are clawing. If they are punching, the claws do not come in contact. Paired with Adrenaline Pounce, unarmed attacks for a ghoul can be very deadly.