Yeah, that's the AM Laser Blimp. AM, as in, "anti-matter", as in, "when it fires, everything goes boom". Which doesn't make any sense, but let's pretend it does
It's basically a concept piece from an old Popular Mechanics plus some crazy Gibson idea from one of his early novels plus me and DRB's speculative ideas about what blimps will get used for in future wars.
It's the only nuke-class thing in the game, and it's really intended to deal with swarms of UltraAssaults in late-game. Thankfully it needs to stay near AA, or it dies.
The sphere is distorted, it's just that it's been cleverly hidden. And there's a seam that's ever-so-slightly off, but in practical terms it's invisible. Yay for mipmaps.
And yeah, I have always wanted to see an Akira-style bubble explosion in realtime, it's one of those things that's impossible with CEGs. I have everything but the clouds / rubble around the edges, and I think I know how to make them, too

That's really just the tip of the iceberg, though. I've discovered how to do something pretty cool recently, and it has a lot of applications.
Oh... and something else I figured out recently allows for AA flak that
actually acts like AA flak, in all ways that matter (aside from a ballistic arc). As in, probabilistic hit ratios and area-saturation, instead of direct hits being the only possible way to damage a target (with corresponding problems against raids in waves). Dunno whether that's going into this beta or not, but it's interesting, and if it doesn't lag too much, could be very useful.
And the HeavyTroopers have to fly high enough to clear buildings, because the cuboid collision tests aren't used to detect aircraft / ground-object collisions at this time. And even if they did, I think it would look really lame for them to constantly do face-plants on the sides of the skyscrapers, since they don't path in air mode, because they're actual planes in that state. So they do the Superman thing and go over them.