The Magnet Beam is a non-lethal weapon of Mega Man's. Dr. Light created it to help Mega Man in his battle againstDr. Wily and the Robot Masters. When Dr. Wily made a copy of Mega Man the clone had all of Mega Man's powers apart from the Magnet Beam (presumably because Dr. Wily did not have access to it like he did the Robot Masters). This advantage over his clone was the thing that saved him when the robot masters charged into the room and destroyed the Mega Man on the ground (while the real Mega Man was in the air using the magnet beam). The Magnet Beam was used to get Mega Man above Wily's spaceship so he could bring down the ship and defeat Dr. Wily once and for all.
Pre-Mega Man uses[]
The Magnet Beam was used to create a cube around Mega Man when he had a dangerous temper tantrum. Mega Man could not break through the cube, even when using all of his powers that he copied from the Robot Masters.