Cain focused around 80% of his Astral Wave on his legs in order to improve his speed. While 100% was an option due to his mastery over Wave Focus, that would leave the rest of his body defenseless, which would be deadly in a situation where hundreds of attacks would come at him every second.
He had not run more than five hundred meters when another tide of Wave Beasts launched toward him, with the one at the lead being a Level 5 Horn Beast.
Even without using his Astral Wave, Cain could have easily defeated a Level 5 Wave Beast, but now such an insignificant opponent presented a genuine problem. If he were to kill it, that would slow him down and weaken his body's momentum, allowing the rest of the horde to gang up on him.
No matter how strong and resilient Cain was, fighting hundreds of Wave Beasts attacking from every direction was nearly impossible. And even if he could, everything would be over once the Wave Champion Beasts reach him.
