Classified

For example, simple misdirection would be way more effective against almost all of them based on the intelligence that he had bought from the Martial Union. The kind of tactics that he would never use against an adult human because humans were intelligent enough to see through blatantly obvious tactics unless they were mentally challenged.

Thus Rui could be a lot less stringent on the quality of his tactics as long as he was cautious and careful despite that.

Though he highly doubted their lowered intelligence alone was enough to develop a technique that allowed him to be extremely effective against them by itself.

('Which means I need to exploit the fact that they have somehow integrated esoteric substances into their bodies.') Rui concluded.

This would require some research on Rui's part. One thing he needed to was gathered more detailed information on the esoteric substances and compounds that the beasts had ingested, turning them into monsters.