i wouldn't call it dbz superpowers, given that normal humans can take down gods. steven erikson's whole premise was "what would a world and culture be like if the gods were real, like in greek and norse mythos, and suffered from all the same weaknesses and failings, after 200,000 years?" the big badasses get dropped like suckaz, and the biggest losers ascend. the idea is that everything really hinges on fate and circumstance, like achille's getting shot in the foot.
also, the central conceit of the book is to relegate perspectives on the characters based on how the world perceives them, not how steven erikson himself perceives them. he WANTS ascendency and the elder gods to be completely confusing and contradictory in their seeming omnipotence and consummate weakness, just like the gods from our own world's mythology. he's said as much in like, every interview