Sid Meier's Alpha Centauri/Units

Alpha Centauri features a Unit Design Workshop which is very flexible in comparison to other Civ games. For each unit, the workshop presents you with choices for each of a unit's weapon (attack strength), armor (defense strength), chassis (speed and terrain movement), reactor (hit points and build cost), and up to two special abilities (but only one until the discovery of Neural Grafting).

Chassis
The chassis is the most important part of the unit. It will determine where it can go (land/sea/air), how fast it goes, and what weapons or equipment it may use.

Infantry

 * Prerequisite: N/A
 * Speed: 1
 * Terrain: land

The default chassis for units. Some units (Crawlers, Formers, Colony Pods) do not display an actual infantryman in the unit graphic, instead using a custom chassis graphic sitting on enlarged treads.

Weapon
Weapons determine a unit's attack strength. Higher attack strengths give a unit better chances in battle. Missile payloads may only be equipped on the Missile chassis.

Chaos Gun

 * Prerequisite: Superstring Theory
 * Strength: 8

Fusion Laser

 * Prerequisite: Organic Superlubricant
 * Strength: 10

Gatling Laser

 * Prerequisite: Superconductor
 * Strength: 5

Graviton Gun

 * Prerequisite: Applied Gravitonics
 * Strength: 20

Hand Weapons

 * Prerequisite: N/A
 * Attack Strength: 1

This weapon is really no weapon at all: when a unit has no other weapon, it will use this.

Laser

 * Prerequisite: Applied Physics
 * Strength: 2

Missile Launcher

 * Prerequisite: Synthetic Fossil Fuels
 * Strength: 6

Particle Impactor

 * Prerequisite: Nonlinear Mathematics
 * Strength: 4

Plasma Shard

 * Prerequisite: Advanced Spaceflight
 * Strength: 13

Psi Attack

 * Prerequisite: Centauri Psi
 * Strength: -1
 * Cost: 10

Quantum Laser

 * Prerequisite: Quantum Machinery
 * Strength: 16

Resonance Bolt

 * Prerequisite: Sentient Resonance
 * Strength: 12
 * Cost: 16

Resonance Laser

 * Prerequisite: Bioadaptive Resonance
 * Strength: 6
 * Cost: 8

Singularity Laser

 * Prerequisite: Controlled Singularity
 * Strength: 24

String Disruptor

 * Prerequisite: String Resonance
 * Strength: 30
 * Cost: 40

Tachyon Bolt

 * Prerequisite: Unified Field Theory
 * Strength: 12

Conventional Payload

 * Prerequisite: Orbital Spaceflight
 * Strength: 12

Planet Buster

 * Prerequisite: Orbital Spaceflight
 * Strength: 99
 * Cost: 32

Equipment
Units with equipment cannot attack - instead they are granted a number of special actions.

Colony Module

 * Prerequisite: none
 * Equipment cost: 10

A unit with a Colony Module can build a new base. Producing a unit with a colony module consumes one population.

Probe Team

 * Prerequisite: Planetary Networks
 * Equipment cost: 4

Units with probe equipment can perform a number of covert actions.

Terraforming Unit

 * Prerequisite: Centauri Ecology
 * Equipment cost: 6

Terraforming units can create all manner of terrain improvements. The Terraforming Unit can be later enhanced with the special abilities

Terraformers are the single most important unit in the game. The AI's poor use of them contributes greatly to its poor performance. Formers are the primary way to make your cities more productive, and are the only way to make tiles more productive (except fungus, which improves with the Centauri techs). Centauri Ecology should always be one of your first techs, or a competent opponent will defeat you.

For comparison, a good unterraformed tile yields 2-1-1 (rolling and rainy, on a river), before nutrient/mineral/energy bonuses are considered. A good terraformed tile yields 0-6-6 (borehole) or 4-1-1 (condensor-farm). A fair unterraformed tile yields 1-1-0 (moist and rolling). A fair terraformed tile yields 1-2-1 (forest).

Supply Transport

 * Prerequisite: Industrial Automation
 * Equipment cost: 8

Supply units can extract one resource from a square and convey it to its home base, and can also be brought to a base to apply its production cost toward the production of a unit prototype or Secret Project.

Supply crawlers are the second most important unit in the game (second to Terraformers). Since they allow you to harvest more tiles, they act like extra population units, but without the drone problems or the nutrient requirements. In effect, supply crawlers are constructed population points, and at 30 minerals are a bargain.

Troop Transport

 * Prerequisite: Doctrine: Flexibility
 * Equipment cost: 4

A Troop Transport, as the name implies, can transport land troops from one place to the other. In combination with the Carrier Deck ability, can also transport air units. The number of transported units depends on the chassis and reactor: Foils can transport twice the reactor strength, Cruisers can transport four times the reactor strength, all other units can only transport one unit at a time.

Having a transport in a sea base along the coast allows units to freely enter and leave the base from the coast.

Antimatter Plate

 * Prerequisite: Matter Editation
 * Strength: 10

Neutronium Armor

 * Prerequisite: Matter Compression
 * Strength: 8

No Armor

 * Strength: 1

Photon Wall

 * Prerequisite: Photon/Wave Mechanics
 * Strength: 5

Plasma Steel Armor

 * Prerequisite: High Energy Chemistry
 * Strength: 3

Probability Sheath

 * Prerequisite: Probability Mechanics
 * Strength: 6

Psi Defense

 * Prerequisite: Eudaimonia
 * Strength: Psi
 * Cost: 6

Units equipped with a Psi Defense always engage in Psi combat when attacked, ignoring weapon and armor strengths. This is useful for defending against opponents whose weapon technology exceeds your defensive technology.

Pulse 3 Armor
''Same as Plasma Steel Armor, but more expensive and with +25% bonus vs. mobile attackers. Alien Crossfire only.''
 * Prerequisite: Adaptive Doctrine
 * Strength: 3
 * Cost: 5

Generally a bad choice of armor, since it costs just as much as Photon Wall, yet is less effective than Silksteel Armor even against mobile attackers. Still, it comes earlier in the tech tree than Silksteel, and might make the difference against an Impact Rover. Provides no benefit to ships except perhaps when defending in a base against a mobile land attacker, since ships are never mobile attackers. The AI prefers Pulse-3 Armor, which needlessly pushes up its unit costs. Disable it or decrease its cost to help out the AI.

Pulse 8 Armor
''Same as Neutronium Armor, but more expensive and with +25% bonus vs. mobile attackers. Alien Crossfire only.''
 * Prerequisite: Super Tensile Solids
 * Strength: 8
 * Cost: 11

Resonance 3 Armor
''Same as Plasma Steel Armor, but more expensive and with +25% bonus vs. Psi attacks. Alien Crossfire only.''
 * Prerequisite: Field Modulation
 * Strength: 3
 * Cost: 5

Mainly useful for combining with Hypnotic Trance on a foil for a great Psi defender. Other than that, see above.

Resonance 8 Armor
''Same as Neutronium Armor, but more expensive and with +25% bonus vs. Psi attacks. Alien Crossfire only.''
 * Prerequisite: Sentient Resonance
 * Strength: 8
 * Cost: 11

Silksteel Armor

 * Prerequisite: Silksteel Alloys
 * Strength: 4

Stasis Generator

 * Prerequisite: Temporal Mechanics
 * Strength: 12

Synthmetal Armor

 * Prerequisite: Industrial Base
 * Strength: 2

Fission Plant

 * Prerequisite Tech: N/A
 * Strength: 1

The default reactor for units. Later in the game, it is ideal for worm-killing units since psi combat ignores reactor strengths, and without a strong weapon, more advanced reactors will usually make the unit more expensive.

Fusion Reactor

 * Prerequisite: Fusion
 * Strength: 2

The first more powerful reactor you can get. The decrease in build costs is noticeable, and your units will be nearly unstoppable until your opponents discover Fusion as well.

Quantum Chamber

 * Prerequisite: Quantum Power
 * Strength: 3

Reactors beyond Fusion are of little use, since the game should well be over by this point.

Singularity Engine

 * Prerequisite: Singularity Mechanics
 * Strength: 4

Clean Reactor

 * Prerequisite Tech: Bio-Engineering

Not to be confused with the unit's Reactor, the Clean Reactor trait comes with Bio-Engineering and while it increases the costs of the unit's construction, it reduces the cost of support.

Deep Pressure Hull
Allows teh unit to function as a submarine.

Hypnotic Trance

 * Prerequisite Tech: Secrets of the Human Brain

This is probably the most popular special ability in the game, perhaps rivaling Clean Reactor. Adds 50% to psi defense, putting defending land units on equal footing with attackers, and turning sea or air units into veritable psi fortresses.

Nerve Gas Pods

 * Prerequisite Tech: High Energy Chemistry

WARNING: using a unit equipped with this in combat is an atrocity. That means if the UN charter is in effect, sanctions will be imposed upon you (nullifying commerce for at least 10 years), and regardless of the UN charter, the opponent on whom you used nerve gas will hate you forever.

+50% attack bonus. Additionally, when attacking a city, kills half of the city's population (round up) if the attacking unit wins.