The Seismatron is an object that appears in the Sonic the Comic series published by Fleetway Editions. It was a machine created by Doctor Robotnik that caused the Mountain of Destiny in the Hill Top Zone to become active.
He used the machine as part of a trap, to lure Sonic the Hedgehog into the volcano and then make it erupt. However, an encounter with a Rexon made Sonic transform into Super Sonic, who escaped the eruption. Super Sonic then managed to contain the eruption, saving the local villagers. The Seismatron itself was presumably destroyed.