The EFF MS development plan was changed due to the theft of the RX-78-02 Gundam and the Pegasus-class, which forced the Federation to base their further development on the RX-77-02 Guncannon and use available operational data from the previously built test units, especially the Gundam. The result was a mobile suit that combined the mobility and close combat capabilities of the Gundam, while retaining the firepower and durability of the Guncannon.

The Light Cannon sported relatively balanced performance, capable of engaging in both close combat and mid range combat.[4] The Light Cannon has modified arms and legs, while the chest, head, and main armament come from the Guncannon. The backpack sported a beam saber on the left side and a beam cannon on the other side. Like its predecessors, the Light Cannon also retains the Core Block System, which can act as escape craft system ensuring its pilot survival.