Also known as: 砲神エグザクソン
Science Fiction manga series by Sonoda Ken'Ichi. Ran for 81 chapters from 1997 to 2004, and was collected into 7 volumes.
Partially published in English as Cannon God Exaxxion by Dark Horse Comics. This English release flipped the original art horizontally to allow for it to be read from left-to-right.