Meka Dragon (also called simply Meka or Mecha Dragon) is the main villain and final boss from Wonder Boy in Monster Land, later returning as the first boss in the sequel Wonder Boy III: The Dragon's Trap and it's remakes.
Meka is a dragon which appeared and terrorized Wonder Land, sending his minions to take over the once-peaceful land, which then became the "Monster Land". The mayor calls upon the help of Wonder Boy, whom he gives a sword so he can set on a journey to defeat Meka and save the land.
Wonder Boy defeats Meka's minions and finally faces the dragon in his castle, initially defeating him. But Meka then reveals his true form, appearing as a robotic dragon from outer space. Wonder Boy defeats Meka, but before dying Meka casts a curse upon Wonder Boy, turning him into a lizard-man. Wonder Boy then sets on a new journey to find the Salamander Cross, the only thing that can lift his curse.