Turning a Weapon Against Oneself

His whole body went suddenly cold, as his stomach convulsed. The vomiting had stopped, but Chen Mu's entire body was aching and limp, without any strength. The side effects of breath control were far more than he had anticipated. That report only included the method to control breathing, with no more detail than that. But he had discovered as soon as he started the training that the report was too simple.

It hadn't brought up side effects, or how to keep the perceptions at a steady frequency, and it hadn't brought up anything about the duration of the state of breath control and related matters, nor anything about the overall situation of the state of breath control.