Guts Man is a civil engineering Robot Master from the Mega Man classic series created by Dr. Light for wilderness reclamation to help with constructions, along with Bomb Man. Guts Man is passionate and likes karaoke, but can be impatient and unreasonable at times. Guts Man and Stone Man are good friends.

Guts Man possesses great physical strength, being capable of lifting and transporting heavy objects like a rock of two tons. In battle, he can use his Super Arm to throw heavy objects, such as boulders and blocks, at his enemies. He can also use his strength to hit his enemies with a powerful tackle, and make the ground shake with his jumps.

Cut Man is one of the first six (eight in Mega Man Powered Up) Robot Masters from the original Mega Man series, created by Dr. Light to be a timber-felling robot. Cut Man first appeared in the first Mega Man game, where he was reprogrammed by Dr. Wily to help him conquer the world. Cut Man is found to be somewhat formal as he addresses other robots as "Mr." or "Ms." (either this or it shows that his A.I. age is younger). His Rolling Cutters are made of highly resistant "ceramic titanium", and are extremely sharp, being easily able to cut through metal.

Elec Man is a Robot Master from the classic Mega Man series. He was built by Dr. Light to control electrical operations. Elec Man manages nuclear power plants and is capable of generating electricity. He can expel over 500,000 volts from his fingertips. Elec Man is very fast and his powerful Thunder Beam can destroy Mega Man in three hits. This was changed in later titles, but his speed and attacking power, along with new lightning-based attacks, still make him a force to be reckoned with, and is still one of the most feared opponents in the original game.

Ice Man is one of the first six (eight in Mega Man Powered Up) Robot Masters from the original Mega Man series. He was built by Dr. Light to perform human-like tasks under extreme climate conditions. This can be done due to the fact he is impervious to chilling sub-zero temperatures. Contrary to popular belief, he is capable of functioning in hot environments, though he is less powerful there.

Fire Man is a Robot Master from the original Mega Man series. He was built by Dr. Light to work in an incinerator at a waste management facility and is able to wield flames that can reach 7000-8000 degrees.

Bomb Man  is a demolition Robot Master from the Mega Man classic series, with the ability to create powerful Hyper Bombs and throw them with startling accuracy, allowing him to destroy most targets with ease. He was created by Dr. Light for mining and construction purposes, as well as to blast away debris so that land could be cleared for construction projects, working in tandem with Guts Man. Bomb Man is a playable character in Mega Man Powered Up and Mega Man's Soccer. He can be fairly reckless with his explosives, due to his relative immaturity, and in Mega Man Powered Up, was shown to have a generally fun-loving, immature and sometimes quite sarcastic personality.

Yellow Devil , also known as Rock Monster or Yellow Demon, is one of Dr. Wily's creations, originally a fortress boss in the first Mega Man game. Consisting of a large yellow blob, he can dismantle himself and cross the screen to attack his enemies. His only weak point is his eye.

Copy Robot copies everything from the Robot Master he's fighting against, except the personality. In the original Mega Man, he always uses the weapon that Mega Man is using. If Mega Man is using the Magnet Beam or Super Arm, the Copy Robot will simply run back and forth, similar to Crash Man.

CWU-01P is an aquatic robot from the first Mega Man game that was originally created for water purification, but is used by Dr. Wily to protect his fortress.

In the first game, there are seven CWU-01Ps that roll through the room inside of bubbles and shoot three bubbles at the enemy. The seven are the same, except that they have different speeds and different colors in the circle on them. They appear one by time, and when one CWU-01P is defeated, the next will be faster. Each CWU-01P defeated removes 4 HP from the total HP.

Wily Machine is the name of the machines that Dr. Wily uses in the end of most games from the original Mega Man series. Most of them have Wily's flying saucer on them and have two forms of attack, with the second form's weak point being the cockpit and Dr. Wily himself. Starting with Mega Man 4, the Wily Machines have been followed up by an escape pod, named the Wily Capsule. Also, starting with Mega Man 4, Wily's Machines have had an unmistakable skull motif.