Seven-Fold Strength!

The moment the invisible waves appeared, David's eyes turned solemn instantly as a knot appear in his heart, palpating with a sense of oppression and wrath. 

David's expression grew stern. This palm attack had made him feel a bit of fear. 

This stranger was obviously only using his physical strength and hadn't even Phased in with any gene yet, but his attack was astonishing enough to shake the heavens and was even more ferocious and dominating than an attack backed with the power of a gene. 

David's eyes sharpened in an instant and he also didn't hesitate to use his full strength. 

The instant he raised his palm, the air shattered instantly as a massive amount of strength began to build up from his palm.

Terrify ripples spread out from his palm and the wind howled with vigour as David slammed his palm against the terrifying attack. 

"Six-fold strength."