Sword Offering

That 'sword offering' (祭剑) was to use a powerful opponent as a target, to treat them as his current shackles. Yue Zifeng had broken his shackles in a single blow, allowing his mental realm to rise. However, if he had failed, it would have very likely formed a heart-devil.
The best target to use as a sword offering was someone incredibly powerful. It was the same old thing: opportunity existed within danger. So for that sword offering, Yue Zifeng had immediately used his full power. Now, he had succeeded. Once he woke, he would find that he had taken his next step.
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