-----
After half a week of training, preparations, and more, Chaos has decided to assess the power of Abyss and Erebus. He had already seen how strong others had grown, but he had been training more with these two because they had grown closer to him.
He had been teaching Erebus how to use physical fighting better, although he wasn't that good at the usage of weapons, and he had more proficiency in using Darkness which made up his materialized body.
Nonetheless, he still could transform into a giant dragon, so Chaos wanted him to utilize this trait to grow more powerful.
Slashing attacks, biting attacks, tail attacks, body slams, anything would do, Chaos made Erebus train this a lot, and didn't let him spam Dark Spears as much anymore through it.
Check "The Protagnist's Sister Is Actually the Strongest"!