Actually, Under Defeat Should have been names: "Zero Gunner 3"
I've seen a video where you fight this huge war ship:

The explosion is cool, but what's more impressive, is the use of never before seen in a shooter, real life physics & meteorological effects, like rain & fog.
Also when the ship explodes, it gets cut in half & slowly begins to sink like it would in real life, rather than just scroll & magically disappear to the bottom of the screen, like in most other shooter bosses.
I hope this gets ported to the DC.
Has anybody played it on the arcades?
How well doesit play compared to Zero Gunner 1 & 2?
I never liked ZG1&2 much my self...