When on kicks something, usually the clear intent is to fling it away but what if one kicked something that couldn't be moved... let's say someone so durable they made a wall feel like paper.
"They didn't so much as flinch."
Art from the moment he arrived expected his opponent to have an active reinforcement so he kick was strong but still didn't have everything put into it and because of such actions, he was only left with a sore pain in his feet as he pulled back his leg and watched the assassin in wonder.
His feets hurted but more importantly, the assassin was motionless as if his kick didn't even tickle them.
It was quite disappointing to say the least since he hoped he had gotten stronger but the saying there were mountains taller than mountains seem applicable here as he twisted his hold on the dagger against their neck and moved foward with a stab.
Crack—!!!