Also known as: ラッシュ, ラッシュ(ロックマン)
A multipurpose Robot Dog created by Dr. Light (Mega Man) to help Mega Man (Character), first introduced in Mega Man 3.
It has a Spring (Object) to help Mega Man jump to hard-to-reach platforms, it can transform into a submarine to facilitate movement underwater and transform into a jet for quick stage traversal, among many other abilities.
It can also fuse with Mega Man, turning him into Super Mega Man (Mega Man).