Clearly, after the brief probing exchange moments before, Isshiki knew he could not defeat Uchiha Chi in his normal state. Therefore, he prepared to unleash his full power to bring this hunt to a conclusion.
Although Uchiha Chi perceived Isshiki's true intent and recognized from Isshiki's initial activation phase that the brief moment of karma release presented a prime opportunity for a sneak attack, regretfully, his own physical state required adjustment following Isshiki's fierce final onslaught and the counter-kick he had received. For the moment, he was entirely unable to step forward and launch an offensive.
Thus, even though he knew in his heart that this was the optimal moment to strike, he had no choice but to let it slip away, watching helplessly as Isshiki continued to unleash his power.
Chapter 423