The plan itself was rather simple however the process and ability to carry out said plan was where the problems started.
Rangi had a feeling he just had to remove that shard from his master's chest and then they would regain control of themselves again. If not that then the one controlling her body would no longer have control over it anymore. This was the hope given how they were allowed to use his master's body as if it were still there their own.
"Hey I know what you are thinking that you can somehow steal this body from me again and get back for it" the woman spoke
At this Rangi was shocked over how they knew what his plan was before he could even attempt it.
"Idiot, as the true owner of this soul why would not I have access to everything that it has to offer" she said laughing
"I know let him see for sure that his beloved master is gone for good by attempt to do whatever he was plotting against you," the king said.