Samuel wasn't certain of what Billy was talking about, but he decided to wait for that. In the meantime, they spared together every day. Both of them were gaining from that somehow, after all.
After two weeks, Billy finally learned the technique that he envisioned when he saw Samuel on the ground and then decided to show him on the next spar. As usual, they started by fighting with their fists alone, and Billy focused on defense. However, when he saw an opening, he punched Samuel in the middle of his stomach… The attack barely caused any physical damage, but Samuel still felt his body getting heavier, and his breathing got haggard. Thanks to that, he was unable to fight like before, and Billy easily landed more hits on him until Samuel lost all his stamina and fell to the ground.
"What was…" Samuel said, visibly shocked.
"Let's see, I will call this skill… Physical Disturbance," Billy said.