Thunder Dragon with Drake
The mount used by Drake the Adventurer is actually an Eastern Wyvern (Draco wyvernesis nipon).
The Eastern Wyvern ridden by Drake—Thunder— was hand-reared from an egg, so it is used to being near humans. It is still, however, and extremely dangerous creature and should not be approached by any without significant training or experience.
Thunder, as an Eastern Wyvern, only has two legs. Its wings are actually its upper appendages and hands, like those of a bat. His body is stouter than true dragons, and it has a tell-tale beak that definitively identifies it as an Eastern Wyvern.
Drake was born into a family of circus animal handlers. He grew up surrounded by lions, tigers, bears, elephants, and every other kind of dangerous creature.
He always had an adventuring streak— even by circus folk standards— so when he found an abandoned dragon egg at the age of 17, he decided to try and hatch it, instead of turning it over to trained scientists or handlers.
Surprisingly, the egg did hatch. Drake was elated to discover it was an Eastern Wyvern, a very rare type of dragon. Wyverns are generally friendlier to humans than other dragons, which was likely the reason Drake survived his first week of parenting Thunder.
Thunder and Drake tour the world regularly. Their stunt-flying show sells out weeks or months in advance. Their death drop— a trick where Thunder flies upside down, causing Drake to plummet to the ground before Thunder gently catches Drake back into his saddle— is said to cause fainting in the stoutest of constitutions.
Mooney, Carla. Dragons. San Diego, CA: ReferencePoint Press, 2011. Print.