Xil'gar Trog's soul is an item that is obtained during The Forgotten Prisoner mystery, and it contains the soul of Xil'gar Trog. The player receives it by bringing a portable phylactery to Xil'gar Trog after answering his four questions. It currently has no known use, but it is heavily implied that it will be useful in the future.
Despite its destroy text, it can be reclaimed for free from Dr Nabanik. Dr Nabanik says he has been conversing with Xil'gar Trog and believes him to be trustworthy.
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