Red: Stiffens its ears to sense danger. The larger its horns, the more powerful its secreted venom.Yellow: Its large ears are always kept upright. If it senses danger, it will attack with a poisonous sting.Gold: It is small, but its horn is filled with poison. It charges then stabs with the horn to inject poison.
Prof. Lotus' Notes: The name is a portmanteau of the Japanese borrowed word for Needle, ニドル (Nedoru), cnidocyte (thing in all poisonous animals) and rhino. Finally, 二度 or Nido in Japanese can be translated to 'two times' and this is often attributed to Nidoran line splitting to male and female.
Gender Differences: Female is light blue and male is purple
Separate evolutionary lines