One of three insects that lives inside the human body. It can tear the gut and twist bones when it goes wild. Master Xifa uses it to guard his temple.
First of all, do not enter this battle without equipping the boys with Bell Bracelets. These prevent silence, which Xieshi casts. Silence is VERY BAD here, seeing as it seals your only option to heal. Have Yuri fuse into Man Dragon to give him a healing skill and elemental advantage over the boss. Have him physical attack and heal if the job's too big for Zhuzhen to handle. Have Zhuzhen defend when not healing, since his attacks and skills are fire-based.
Along with the other two bosses of the Temple Ruins, Xieshi is meant to be a reference to the Three Corpses, a Taoist physiological belief that demonic creatures live inside the human body, and they seek to hasten the death of their host.
It's name is derived from the characters, "血" (Blood), and "尸" (Death, Corpse, Remains).