Master of Orion II: Battle at Antares/Hiring Leaders

From time to time you'll get opportunities to hire Leaders who will enhance the performance of your economy or your military, or occasionally both. These characters are mercenaries - they work for anyone who will pay their fees, which come in 2 parts: a one-time hiring fee, usually quite large (rather like a transfer fee in football); and a salary per turn.

The influence of Leaders gradually declines as your technologies improve in the relevant areas. This reduction is most significant for Creative empires, as they get all the techs at each level; for other empires, Leaders may fill some of the gaps in their range of techs. Many abilities go up a level as Leaders gain experience (usually about every 30 turns), which reduces the rate at which they may be overtaken by technology.

Getting the right leaders in the early game can be major advantage, while hiring the wrong ones can simpy drain your finances. Usually the best leaders appear later in the game and are really expensive - but by then you will seldom need them.

Leaders have 3 types of ability, in various combinations:
 * Ship Leader abilities, most of which are only useful if the Leader is in command of a ship.
 * Colony Leader abilities, most of which are only useful if the Leader is in command of a system. These abilities benefit all your colonies in the system.
 * "General" abilities, that can appear in both Ship Leaders and Colony Leaders.

The "general" and Colony Leader abilities are mostly relevant to managing your economy. It's also sensible to present the Ship Leader abilities here, since:
 * They cost money, which is a major consideration in the early game.
 * Some Ship Leaders have abilities that have other benefits, including for your economy.

Managing leaders
An empire can have at most 4 Colony Leaders and 4 Ship Leaders. If you don't hire a Leader when he / she first appears, he / she waits in your Officer Pool for 30 turns. That has an important consequence - if you have 3 leaders of a type (Colony or Ship) and a 4th appears that you don't want, dismiss him / her immediately, because no more Leaders of that type will appear while there are no free slots in your Pool.

For governments other than Unification, the Officer Pool is effectively a lounge in the Capitol, which is initially on your homeworld. If a non-Unification empire loses its Capitol, either by sabotage or because the homeworld is invaded or destroyed, no new leaders will appear until you build a new Capitol; you should in any case do this as fast as possible because your whole empire will suffer a morale penalty for as long as there's no Capitol. A Unification empire has no Capitol, and the Officer Pool is initially somewhere on the homeworld. Unfortunately the manual does not say what happens to leaders in the Officer Pool if the Capitol is destroyed or a Unification empire's homeworld is destroyed or captured, nor does it say where the new Officer Pool is if a Unification empire's homeworld is destroyed or captured.

Colony Leaders who need to be assigned to a system are ineffective until they arrive at that system. Leader assigned to the system containing your Officer Pool "arrive" instantly; Colony Leaders assigned to other systems take 5 turns to arrive. A system can have 1 Colony Leader, so if you assign a new Colony Leader to a system that already has a Leader, the incumbent has to return to the Officer Pool; and does so immediately, so the system is without a Leader for 5 turns.

Similar rules apply to Ship Leaders: if the ship is in the system containing your Officer Pool, he arrives instantly; otherwise he takes 5 turns. There's one other rule for Ship Leaders: in order to refit a ship that has a Leader, the Leader must first return to the Officer Pool.

General abilities
These are the ones that both Colony and Ship Leaders may have.

Assassin
Has a chance (small) of assassinating an enemy Spy every turn.

Improves with experience.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Assassin Leaders, enemy Spies die faster.

Commando
Increases the strength of all ground combat units in the system where the Leader is stationed, including Marines in ships and Starbases etc.

Improves with experience.

This ability works while the Leader is in the Officer Pool but not while travelling to his system / ship. And if you have several Commmando Leaders in the same system, each of them boosts your troops.

Diplomat
Improves other empires' attitudes towards yours, making them less likely to attack you and more likely to agree to your proposals.

Improves with experience.

Useless to Repulsive empires.

Famous
A Famous Leader increases the chances of other Leaders applying to join you and decreases their hiring cost and, in most cases, their salary. Has no effect on the salaries of Leaders you've already hired.

Improves with experience.

In description of Leaders, Famous is described as "-nBC", i.e. by how much this Leader reduces the hiring fees of other Leaders.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. But if you have several Famous Leaders, only the most Famous affects the frequency and costs of new Leaders.

A very useful ability, especially if your empire is Repulsive and therefore would otherwise have a poor choice of Leaders.

Megawealth
Contributes a flat 10BC per turn. The cheaper Megawealth Leaders pay off their hiring fees in 8 turns.

This does not increase with experience.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Megawealth Leaders, each of them pays you 10BC per turn.

Researcher
Makes a flat-rate contribution (fairly small) to your research.

Improves with experience.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Researcher Leaders, each of them boosts your research.

Spymaster
Increases the effectiveness of all your Spies operating in other empires, i.e. on espionage and sabotage, not on defense.

Improves with experience.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Spymaster Leaders, each of them boosts your offensive Spies.

Tech knowledge
Gives 1 to 3 free techs when you hire the Leader. This is a one-time benefit.

Telepath
Increases the effectiveness of all your Spies operating in your empire, i.e. on defense but not on espionage and sabotage; protects all colonies in a system against Mind Control.

Improves with experience.

The spying boost works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Telepath Leaders, each of them boosts your defensive Spies.

The defense against Mind Control works while the Leader is in the Officer Pool but not while travelling to his / her system / ship; if in the Officer Pool, the Telepath protects the system containing the Officer Pool. Having several Telepath Leaders in the same system is wasteful.

Trader
Increases the cash income from Trade Treaties.

Improves with experience.

This ability works while the Leader is in the Officer Pool or travelling to his / her system / ship. And if you have several Trader Leaders, each of them boosts your income from Trade Treaties.

Useless to Repulsive empires.

Colony Leader abilities
All of these abilities work only while the Leader is working in a system, not while he / she is in the Officer Pool or travelling to a system.

Environmentalist
Reduces industrial pollution at all colonies in a system and so boosts your effective industrial production.

Useless for colonies whose populations are entirely Tolerant.

Farming
Boosts farming productivity of all colonies in the system, including for Natives and Android Farmers.

Improves with experience.

Useless for colonies whose populations are entirely Lithovore or Android, or where farming is impossible.

Finance
Increases the "normal" income of all colonies in the system, i.e. excluding income from gold, gems, Trade Treaties, Trade Goods and sales of surplus food.

Improves with experience.

Has little or no effect at colonies with a "normal" population below 8 (excluding Natives and Androids).

Instructor
Increases the rate at which all your Marines and all your other Leaders gain experience.

Improves with experience.

Possibly not a huge benefit, as its effects are gradual and improving technology makes Leader's abilities and Marines' experience less important as the game progresses.

Medicine
Increases the population growth of all colonies in the system; does not apply to Natives or Androids.

Science
Increases the productivity of scientists, i.e. population engaged in research, at all colonies in a system.

Improves with experience.

Spiritual
Increases the morale of non-Android population at all colonies in a system. This can be surprisingly powerful, see Strength through Joy for explanation and examples.

Improves with experience.

Useless for Unification empires.

Tactics
Improves ship's offensive ability (accuracy) and the strength of ground troops in the system.

Ship Leader Abilities
It's important to distinguish between abilities that benefit only the Leader's ship and abilities that benefit all ships in a fleet that contains the Leader's ship.

Engineer
Benefits only the Leader's ship.

Increases the rate at which the ship's shields regenerate and repairs some damage during comabat, i.e. similar to an Auto Repair Unit but does not take up space in the ship. Repairs all battle damage immediately once a battle is finished; this is no advantage if you have the Automated Damage Control technology.

Helmsman
Benefits all ships in a fleet that contains the Leader's ship.

Improves the defensive abilites of all ships in the fleet, i.e. makes it harder to hit them with all types of weapons. Least effective against Fighters /  Bombers /  Heavy Fighters, as these fire at zero range; but you should shoot these units down as fast as possible anyway.

Fighter Pilot
Benefits Fighters / Bombers / Heavy Fighters carried by all ships in a fleet that contains the Leader's ship.

Increases the defensive ability (evasiveness) and beam weapon damage of all Fighters etc.

Galactic Lore
Provides constantly up-to-date information on all planets in the galaxy: type, maximum population, actual population, any fixed defenses. Does not show Space Monsters, but you can assume any really desirable unoccupied planet is guarded by a Monster, and if the system's name is "Orion" you know it's the Guardian (yes, the Guardian is a Monster in terms of the way the game works).

Improves the defensive (evasiveness) and offensive (accuracy) abilities of all ships in the fleet when fighting monsters and Antarans.

Up-to-date information on all planets is useful at all tech levels.

Navigator
Benefits all ships in a fleet that contains the Leader's ship.

Increases the fleet's speed by 1 parsec per turn, and enables the fleet to ignore the movement restrictions caused by:
 * nebulae. Passing though these normally slows ships to a snail's pace no matter how fast your drives are.
 * black holes. Normally it's impossible to travel on a route that passes through a black hole, and travelling on a route that passes close to  a black hole creates a risk that some ships will be sucked in and lost.

This ability remains useful even at high tech levels, if the map has a lot of nebulae and / or black holes in places where they would seriously obstruct your movements. This is something you can work out fairly easily from the Galaxy map.

Operations
Provides extra Command Points for your empire, so you can run a bigger fleet without having to buy Command Points at 10BC per CP.

Can be a huge advantage in the early game, especially for blitzers. Insignificant later, when you have more CPs and a much larger income.

Ordnance
Benefits only the Leader's ship.

Increases the maximum damage inflicted by all of the ship's weapons, except Fighters etc.

Security
Benefits only the Leader's ship.

Improves the combat strength of the ship's Marines when defending against boarding parties; similar to Security Stations but does not take up space in the ship.

No advantage if the ship's shields are still operational on the side facing the enemy, as shields block all attempts to board.

Weaponry
Benefits only the Leader's ship.

Increases the accuracy of the ship's beam weapons. Useless for ships with no beam weapons.

Loknar, the last Orion
If you beat Orion's Guardian, you get a very powerful battleship commanded by Loknar, who has Galactic Lore and insanely high skill levels in the following abilities: Ordnance; Weaponry; Helmsman (benefits the whole fleet of which his ship is part); Fighter Pilot (benefits the whole fleet of which his ship is part, provided they carry fighters; Loknar's ship does not).

Loknar's main weakness is that he is not a Navigator. He also does not improve with experience, but starts at such a high skill level that this is not a problem.