Dreamsnake

Dreamsnakes (aka Nagas) come into the real world out of a bad feather Takshaka. According to the laws of exchange, every time something is lost or left in the Vurt, a snake would escape. They are green and violet, their size vary greatly, some reach up to 12 ft in length. 
The only known cure for a dreamsnake's bite is snakeweed.
The shimmyographers like Icarus Wing keep dreamsnakes in tanks to produce dream mist which is used for making Vurt feathers.
The Scribble had been bitten on the ankle by a dreamsnake during a trip when he was 17, with certain amount of Vurt remained in his organism thus enabling him entering the Vurt and traveling between the theaters featherless. The wound kept acting up every time The Scribble approached a dreamsnake. 
Tristan kept a line of dreamsnake skins pinned over his fireplace.
The Beetle killed a dreamsnake once and wore its head on his lapel as a decorative trophy. 
Dozens of dreamsnakes' carcasses were found in the kitchen of Das Uberdog's house.