Here is the unit list, as of now:
Lord: The Lord is the Commander-equivalent. You only get one. The Lord is "blessed" with a number of remarkable powers, and can build some very special things that nobody else can- and can build at extreme distances, allowing it to project power. However, the Lord does not have anything like a D-Gun, and is relatively easy to kill.
Queen: Second only in overall power to a Lord, the Queen possesses strange but useful powers. Strictly a strategic-level unit, used with care, the Queen is the most powerful offensive weapon you can possess. The Queen is very costly to maintain, however, and is not invulnerable.
Knight: The Knight is the epitome of close-combat prowess and brute strength. For those of you who've played NanoBlobs before, the Knight will feel fairly similar- it is still armed with its fearsome flamethrower, still self-heals, and still gains experience at ridiculous rates. Knights dish out more damage than most other units, by far, and are one of the few units that can take on Rooks consistently and win on cost-effectiveness.
Wolf: The Wolf is a raider, pure and simple. The Wolf has been given a weapon that maximizes its abilty to run-and-gun, taking out whole economies in a flash. Wolves are the only unit capable of crossing water at high speed, but not the only unit capable of crossing water.
Spire Rook: The Spire Rook is a defensive unit, designed specifically to take on Wolves and Knights. In numbers, their combined firepower is enough to stop large numbers of attackers, and they aim very quickly. They move very, very slowly, however, and take quite awhile to build, so they must be placed carefully and advanced with finesse.
Round Rook: The Round Rook is an offensive unit, whose primary purpose is to destroy Spire Rooks and Anti-Archers. It is countered only by the Wolf and Knight, which can destroy it fairly easily, or a lucky Archer that can get close enough.
Bishop: The Bishop's goal is to delay the foe. It has a number of tools at its disposal that allow it to do so.
Archer: The Archer, along with the Knight, and Round Rook, provide the main structured offense. Firing long-range weapons that can kill most other units fairly quickly, the Archer is best used in large blocks where it can saturate the ground- it is not terribly accurate.
Anti-Archer: The Anti-Archer is a bulky, slow-moving unit that has a high-powered, very short-duration pulse laser mounted, which can destroy an Archer's shells in mid-flight.
Light Unit Beamer: These can build the common units, and can be placed just about anywhere. However, compared to a Lord, they build slowly. More quickly than Sheep, but not by a great deal. Good for pumping out Archers and Wolves, though.
Heavy Unit Beamer: These cannot be built anywhere except for geothermal spots. They build as quickly as Lords, and can build almost all of the units, except for the Bishop and the Queen. Taking these spots is a good way to achieve victory on maps that feature them.
Sheep: The core of your economy, the Sheep is weak, defenseless, and yet essential. Sheep can move, which is their primary way of avoiding death. Sheep can build certain units, albeit slowly.
MegaSheep: a "step above". the MegaSheep provides extra resources- at a price. It cannot build units, and explodes rather violently. It has extra armor, and is able to defend itself (weakly), but it is very slow.
Flying Sheep: A Sheep that puts out fewer resources than a standard Sheep, and cannot build units, but it can fly. Good for hiding an economy somewhere, or as a scout.
... subject to revision, editing, and other Good Ideas
