Beetler resembles a medium-sized beetle with large green eyes, a light blue kimono worn except for the right half, and armor of the same color in his wrists, legs and head. He also wears an orange scarf.
Beetler has the ability to summon Stag Beetles with a simple call.
He can yet again be found on Mt. Wildwood, but during the day as well.
Beetler can also be befriended during the "Which Beetle's Better" request if a ★Miyama Stag is given to the boy that prefers stag beetles. After getting to Rank B and going back to the Harrisville school in the present, Beetler will appear and will be automatically befriended.
"Beetler" is a combination of beetle and battler. "Kuwanobushi" translates as "plow's warrior" (referring to the meaning of kuwagatamushi).
Beetler is based on a stag beetle, or kuwagatamushi (literally "plow-shaped insect"). A popular species among bug catchers and insect fighting fans, this insect's distinguishing feature is its large, antler-like mandibles, which it uses to wrestle with other males for dominance (hence its English name). Ironically, despite their size and power the mandibles are more suited for lifting and throwing than biting and are mostly harmless to humans, whereas the female beetle's smaller mandibles will inflict a more painful bite. Though they're not aggressive towards humans, stag beetles will fight fiercely against males of their own kind and even other large beetles, like the kabutomushi (see Rhinoggin#Trivia).