Although the Phantom Fruit Beast appears weak on the outside, according to historical records, it is the only spirit beast that has four stages of evolution. Currently there's only a record up to it's third stage of evolution. As for the fourth stage, it still remains a myth.
The Phantom Fruit Beast is seen when Bai Shui Er, attempts to poke its eye ball, it changes its eye into a trap. After Bai Shui Er says that, almost poking it was scary and Golden Spirit Child noting it has a temper its eye starts to glow.
Later on the Phantom Fruit Beast came across Bai Shui Er, were they was confronted by a departed spirit. Until saved by Cao Yan Bing and Dian Wei.