Wyverns

Wyverns or Bastard Dragons are often mistaken by the greater populace for Mortal/Earthborn Dragons, but in truth they are only related by the features they share and that they come from the draconic species. It is said that Wyverns were created by the gods from the scales and hairs of dead dragons as an attempt to create a species of dragon that would be under their control, as normal dragons are unruly and only listen to those they deem worthy, but after the process was done this new "dragon" only had two limbs instead of four like the other dragons and were smaller than their cousins. Wyverns spit acid and venom, unlike dragons, it is theorized that the reason for this is that since they were made from the body parts of dead dragons, whatever rot or decay may have set in during their creation may have manipulated the Wyvern's breath into breathing/spitting acid and venom.