Guidor is the former mentor of Elena. During the quest Biohazard, Elena sent an adventurer to consult him about the plague affecting West Ardougne. When word of a plague carrier reached Varrock, the area he was living in was sealed and his wife had him confined to his house, claiming that he was dying and would only allow a priest in to give him his final rites. The adventurer smuggled a plague sample, some touch paper, ethenea, liquid honey and sulphuric broline to him under the guise of a priest, where he confirmed Elena's findings that the plague afflicting West Ardougne was fake.
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