Quality over Quantity

While Kane fell into deep consideration about how he ought to allocate his time, Rui had far more clarity on what he wanted to spend his time training. There was only one answer under his current circumstances after having spent three years in the Beast Domain.

"Time to expand the Yggdrasil System." 

Rui found himself perched atop a mountain on the Mellow Manifold with closed eyes and crossed legs. The calm serenity that overtook him on the outside was in sharp contrast to the maelstrom of thoughts that flashed through his mind.

Domains and monsters.

A match made in heaven.

He had already discovered that one of the weaknesses that monsters had was heavy environmental requirements and, consequently, environmental weaknesses. Unless humans had no specific or particular environmental requirement or weakness of any kind, these beasts were strong specifically because they evolved for given environments.