These lumbering hulks are slow, heavy--and deadly, equipped with three Intruder planes that rain down Hornets. Two or three of these--escorted with a healthy mix of other naval units--can devastate a base, as the Intruders restore to full health after each run, and are even re-supplied at no cost to the player if destroyed. All around, the best unit for kicking off a full-scale shore assault.

Fast and invisible to enemy radar, the Dolphin sports a sonar amplification device that sends powerful sonic waves that damage waterborne foes. Its speed and maneuverability make it an excellent escort unit for more heavy-duty units such as the Aircraft Carrier, and is especially useful against submerged units such as Giant Squids or Subs.

Building the Air Force Command gives you the ability to launch Paratroopers, which are generally "charged up" every three minutes, after which you can drop them anywhere on the map. They're essentially a dose of free infantry to be dropped anywhere on the map you like. You can use them in a couple ways. Try dropping them directly into your enemy's base as a diversionary tactic while you forge a larger battle plan, or deploy them anywhere else on the map to "store" them up for a later rush.

Virtually powerless against infantry and structures, the Tank Destroyer specializes in -- you guessed it -- destroying tanks. Armed with special armor-piercing shells, Tank Destroyers are best used as a defensive unit, especially against opponents who are fond of tank rushes. Mix a few of these in with the defensive units at your base, and watch the incoming columns of tanks go down.

Boasting the best air force in the world, Korea is home to the elite Black Eagle Jet, a souped-up version of the Harrier. While the speed of the Black Eagle is the same as the Harrier, the Eagle's armor and firepower are considerably stronger, making it invaluable as an offensive unit, best used against enemy structures. After taking out an opponent's air defense, a few well-placed Black Eagle strikes against his Ore Refineries can quickly cripple a base. Combine it with a ground attack using waypoint mode to overwhelm your opponent.

Technically more of a structure than a unit, the French Grand Cannon is the ultimate base defense: one darn big gun that fires devastating, long-range concussion shells. The units relatively slow reload time make it wise to have more than one handy at a distance from each other for maximum effect. Its most glaring weakness its vulnerability to aerial attacks, so it's always wise to back up your Grand Cannons with anti-air support--and maybe a few Grizzlies in case there's a rush.