封谞 / Feng Xu (late Han)
封谞 / Feng Xu enters the wiki through Hanji 924 as one of the palace eunuchs exposed as an inside contact for 张角 during the Yellow Turban emergency.
His case matters because it gives 汉灵帝 direct evidence against the court narrative that party figures were the main rebellion danger. The emperor can scold the attendants by contrasting loyal party figures with Feng Xu and 徐奉, but the source shows that this recognition does not break the broader protection around the 十常侍.