Dilan had learned a lot from the Great Wise and all the books and tomes he had read in the City of Trials' library.
His knowledge had increased by leaps and bounds.
This didn't really change his personality, let alone his intelligence but it was still very helpful, in many ways.
The pure races were considered Flawed Races by Dilan. Being unable to lie might be helpful in certain situations but sometimes he felt that it was necessary to lie to protect his family and friends.
As for killing without good reason, Dilan had done so very often. He killed various monsters, no matter whether they were vile or not. His great reason had been to collect their Essence crystals and become stronger.
In the long process, his reasoning was good enough, but a mountain of millions of corpses was piled up behind Dilan and the other human Demi Gods. Their rapid advancement was given to them through the strength they gained from the beings they killed.