This all originate to a local young man who uploaded a video clip online to express his sad feelings on a bad date he had earlier that day. He repeatedly murmured how bad he feels at the moment and wants to cry. And he continued to ask why it.
But to the opposite, you just can't stop laughing after watching it because it does sound like he's kept saying " blue skinny mushroom", which makes little sense but silly in such an upset moment.
The funny comparison in the clip inspires Chinese netizens' creativities into a memes wave.
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网友们因此掀起各种模仿秀和恶搞,把“蓝瘦香菇”的欢乐推向高潮。
It is even printed on the NZ's 50 dollar note.
Blue mushroom stamp issue one of a series of six NZ fungi 2002
When "Pen Pineapple Apple Pen" (PPAP) meets "blue skinny mushroom", how does it look like?

Source: weibo
A celebrity version:
A Rap version:
While some can't stop enjoying the internet sensation caused, others start to search for real blue skinny mushroom on the world. They've found there is a literally blue and skinny mushroom called Entoloma hochstetteri in New Zealand.

Image Credit Flickr User Roberta WB Source: Image Credit Flickr User Roberta WB

Image provided courtesy of Reserve Bank of New Zealand Source: Image provided courtesy of Reserve Bank of New Zealand

Source: www.terrain.net.nz
Further more, the young man from the original video opened his official weibo account with Sina Weibo microblog site after his upset face was widely spreaded on internet. He looks quite happy now with over 51k followers and looks forward to starting his own first livestream tonight.