MROB-6720M is a battle theme in Mother 3. It is mainly techno, although the heavy use of drums results in a heartbeat track that is fairly even. This song plays during battles against Li'l Ms. Marshmallow and Unwelcome Gusts and the unused enemy Green Train . The song is a remix of Sanctuary Guardian (Track) from Earthbound which is in turn a remix to Battle With a Dangerous Foe from MOTHER.
GENE163-1425 is the harder version of MROB-6720M. It is roughly the same song, but sudden outbursts of a different part of the song occur three times. At these times, the rhythm speeds up for 3 beats, stays the same, and slows down, respectively. Also, near the end, the rhythm slows down. This version first plays when battling against Mr. Genetor and Boa Transistors.