Underworld 4

Underworld 4 is the twenty-ninth level in Global Defense Force and its port, Earth Defense Force 2: Invaders From Planet Space. The full-scale attack on the Buggernaut nest beneath an unspecified town reaches its apex as several teams make it to the queen's chamber. The Buggernauts have become desperate.

Four unseen characters are noted in this level: Hojo, Sono, and two others. Hojo appears to die with his squadron, and Sono panics after his squadron is killed (possibly the same squadron as Hojo's); despite Ops' best efforts to calm the soldier, he is inconsolable and dies when he is surrounded.

Ultimately, this is the most successful of all similar missions in the series; although suffering the typical 50% casualties that come with these mission sets, the queen here is perhaps the easiest occurrence to battle against, and an actual nest gets eliminated.

Basic Information
Location: Unspecified

Explanation:

Previous Mission: Underworld 3

Following Mission: Dragon Worms

Enemies

 * Ants
 * Bau
 * Flying Ants
 * Queen
 * Eggs

Strategy
Despite what this level claims, the area is not in fact a maze - luckily, there is one straightforward path, making this far easier to navigate than some similar levels in other titles in the series, such as its equivalent in Earth Defense Force 4.1: The Shadow of New Despair.

The mission consists of four waves, although these mark the path to follow down to the queen's chamber. First you must drive through three small clusters of Ants, which will then spawn two clusters of Bau next to one another. Note that despite it looking like the path splits here, both these tunnels converge up ahead again and continue on as one. Once both of these Bau clusters are taken care of, another group of Ants will appear. Take care of these Ants and the next enemy blips on your radar will lead you to the queen's chamber.

Despite how dangerous this area may appear from the radar, it is not much to worry about. The Queen will be trapped in her room as usual, and can still fling large globs of acid into the adjoining tunnel, but they seemingly are less effective than other queens met in the series, and neither appear to affect Pale Wing flight capabilities nor do damage over time. Hitting the queen with any weapon will draw out her Flying Ant entourage, which you can easily dispatch one by one by leading them into the tunnel and around the nearby corner. Once these are dispatched, you will still see many red blips on your screen; however you will not have to worry about these at all, especially if you are fairly precise with your weapon - it is hard to miss such a large target, even with the sensitive controls found in this title. Once you have dispatched the queen, you can enter her chamber and discover what those other red blips actually are: Eggs.

Eggs are a unique enemy in the series. They are non-hostile until attacked, upon which they will hatch after a few seconds to reveal a single Black Ant. If you take your time and attack only one egg at a time these will be a cinch to take out. Once all eggs have been destroyed the mission will end.