The Atomic Heat Ray Gun is a mobile weapon which first appears in Mothra.
As the titanic Mothra Larva entered Tokyo, the JSDF followed, attempting to attack the larva but being thwarted at every turn. Damaging Tokyo Tower, the Larva formed a gigantic cocoon around herself. It now was the turn of the Atomic Heat Ray Guns to attack. Firing their beams at the silky capsule, the intense heat caused the cocoon to burst into flame. However, rather than killing off Mothra, the heat provided the energy for Mothra to fully transform. Breaking free of the cocoon, Mothra flew away from Japan, towards New Kirk City, leaving a bewildered (but otherwise relieved) Japan in her wake.
- The Atomic Heat Ray Guns appear to be based off the Markalite Cannons, as they share the same satellite-disk features. As a result, they also share close similarities with the Maser Cannons. In Godzilla Against MechaGodzilla, it is revealed that the Atomic Heat Ray guns were precursors to the Maser Cannon in-universe, as their technology was later developed into that used for the Maser Cannon.
- The Atomic Heat Ray Gun seems to be an updated version of the Atomic Heat Cannon, as they both shoot atomic heat as a main weapon, and have large golden sattelite-disks as firing mechanisms.