Quoted from Gundam.Info
"The crew infiltrates the space fortress Ambat. Fortress Commander Gerra Zoi pilots the top of the line Defurse to defeat the Gundam.
The Gundam and Defurse have a final battle inside the fortress, but moved by his hatred towards the UE, Flit finally corners Gerra. But a surprising truth awaits him. What does Gerra tell them about the earth's cursed past? Who are the UE? The truth is revealed!"