'Am I strong?'
That was a crucial question for Cain, as it involved a core belief. For him, power was everything. With it, he would never feel hopeless, like when the Atrox God fired that spell against the Imperial Lightning Fort, or impotent against injustice like with Salar Jones.
For most people, power was a means to a goal, but Cain's mind worked differently. His goal was to obtain such a monstrous power he would not have to wish for anything, as he could do it all. So strong that nothing could stop him, and he could destroy every obstacle in his path.
Power on its own was neither good nor bad, and it depended on the hands of the user. A righteous man would bring forth a period of justice, while a wicked man would unleash a wave of sin and corruption.
Cain was not so narcissistic as to believe he would be a champion of justice after gaining enough power, but he was sure that he would butcher all evil in his path.