Strongest hero lore-wised?

According to the Diablo wiki, he decided to weaken the nephalem after lilith went pyscho on the other renegade demons and angels when they suggested wiping out the nephalem to protect themselves from the prime evils and anguris council, which resulted in him banishing her to the void. In fact most didn’t know about the tempering, and thought they were succumbing to some kind of plague, those that did know and protested were crushed by Inarius. In any case, they slowly grew weaker over the generations since. This also reveals that not all nephalem, like angels or demons, are equal in power, and that some are stronger than others.

While the wiki does not say that diablo lost on purpose, as he needed the prince Albrecht because he was too weaken to take control of leoric, it does say that Aidan, the hero, stabbed himself in the head with the soulstone as it had been too badly damage to contain Diablo forever anymore.

I can neither confirm nor deny that Aidan might have influenced the D2 fight at all, but the wiki said that Aidan’s will was subverted by Diablo, so no idea if that is true or not.
Sources: Nephalem | Diablo Wiki | Fandom Diablo | Diablo Wiki | Fandom

wiki’s dont mean jack.