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Chaos plan was rather simple, he had decided to devour Valen from the inside out. However, because this plan had the big flaw of Valen not being an idiot, he would had been found out either way by him. Valen was incredibly sharp and smart, and this was why Chaos was sure that he would realize that Chaos was inside his body and soul sooner if he wasn't being distracted by Chaos' allies.
This was why it was very important to not only disrupt his movements, but also his thoughts, this was why he was constantly attacked and without being given any chance to think about anything else than that. Like this, Chaos was able to slowly get through his defenses, and when things finally reached their climax… he finally managed to devour all of Valen's soul and his entire body became his.
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