Robot Junior is a mecha

Mecha

A mech , is a science fiction term for a large walking bipedal tank or robot, including ones on treads and animal shapes.-Characteristics:...

 piloted by Kabuto Shiro in the manga

Manga

Manga is the Japanese word for "comics" and consists of comics and print cartoons . In the West, the term "manga" has been appropriated to refer specifically to comics created in Japan, or by Japanese authors, in the Japanese language and conforming to the style developed in Japan in the late 19th...

 and anime

Anime

is the Japanese abbreviated pronunciation of "animation". The definition sometimes changes depending on the context. In English-speaking countries, the term most commonly refers to Japanese animated cartoons....

 Great Mazinger

Great Mazinger

is a manga comic book and anime television series by manga artist Go Nagai, made as a direct continuation of the successful Mazinger Z series...

 that first premiered in episode 25. The robot resembles a little boy in a baseball jersey, and the "docking vehicle" that Shiro pilots to connect with it is shaped like a baseball cap

Baseball cap

A baseball cap is a type of soft cap with a rounded stiff brim. The front of the cap typically contains designs or logos of sports teams ,...

. Robot Junior's special attacks include "Iron Batter", a parody of both Mazinger Z

Mazinger Z (robot)

Mazinger Z is a fictional mecha from the anime and manga series of the same name, created by Go Nagai. Within the story, Mazinger Z was created by Professor Juzou Kabuto and piloted by his grandson Kouji...

's "Iron Cutter" special attack and Great Mazinger's "Mazinger Blade" special attack, in which an iron baseball bat

Baseball bat

A baseball bat is a smooth wooden or metal club used in the game of baseball to hit the ball after the ball is thrown by the pitcher. It is no more than 2.75 inches in diameter at the thickest part and no more than 42 inches in length. It typically weighs no more than 33 ounces , but it...

shoots out of Robot Junior's shoulder, which Robot Junior can catch and wield as a weapon. In Super Robot Wars D Robot Junior and Boss Borat have Combination attack where Robot Junior take the bat and Boss Borat holds out a Tee ball for Robot Junior to hit but misses and Hits Boss Borat's head off turning it into a projectile.