X-COM's combat role is served by highly trained X-COM Agents. Agents are made up of brave men, women and artificial humans and are Mega Primus' front-most line of defence against the new dimensional alien invaders. New to the X-COM series is the addition of three distinct races that can be used in combat.
Agents come in three flavours of races: humans, hybrids and androids. Each race has a unique trait or ability that can used to your tactical advantage.
Humans have been around since well before recorded history. They are the most common of the three races available for hire. While they have no unique race related skills, they start with strong to average physical abilities, allowing them to quickly become adept fighters.
The humans main weakness is their limited psionic abilities. With low psi defence, they will always be the most vulnerable of the three races to alien psi attacks.
Human recruits have no political dependencies that prevent them from offering their services to X-COM.
Hybrids are the result cross breeding humans with Sectoids. They have sectoid eyes and/or forehead ridges and baldness is common. They are mentally powerful but physically weak.
Although psi is their key racial ability, expect your hybrids to spend some time in the psi-gym before they become truly useful at psionic attacks.
Their weak physical abilities often makes them liabilities in combat. However, after some time in both the psi-gym and physical training, hybrids have the potential to be the most powerful of the three races.
Hybrids are backed by the Mutant Alliance, a political group that promotes the welfare of Mega Primus's half human and half sectoid citizens. Being on good terms with the Alliance will allow new hybrids recruits to occasionally appear for recruitment.
|Requirements: Non-hostile relations with Mutant Alliance|
The Androids are the oddball of the three races employed by X-COM. Androids are artificial humans who have reached a point of awareness and believe them selves to be alive.
An Android's abilities are based on its construction and programming and they are not able to improve physically in any way. Though this may seem to limit their usefulness, androids have good starting stats and are reasonably good fighters from the moment they are hired. Also unique to the Androids are their immunity to psionics. Brainsuckers also do not actively attack them.
Androids are backed by S.E.L.F. - the Sentient Engine Liberation Front - a political union fighting for Androids to have the same rights as humans. X-COM needs to be on good terms with them before they will allow androids to enlist. Even so, quantities of recruits made available are very limited.
Note that, while there is a separate damage modifier category for androids, it is not used.
|Requirements: Non-hostile relations with S.E.L.F.|
Apparently, and for purposes of rank progression, all your hired personnel count toward the soldier limit, including scientists (which are presumably assigned the rank of Rookie, since it seems that scientist promotion does not take place in Apocalypse). Therefore, it is possible to have only ranked (i.e. higher than Squaddie) Agents if the total staff limit was reached through hiring scientists to fill the ranks. Check the discussion on the Agent Ranks page for more information.
Recruitment Algorhythm explained
All units are generated on a list which has a total of 180 slots, so you can have a maximum of 180 units of any type. There is a cap of 100 agents and 50 engineers. I do not know whether there is a hard cap of number of scientists, as I always end up with 100 agents, 50 engineers, and 30 scientists in total.
The slot that the unit fills is set in stone when it is GENERATED, not hired. Once a unit is placed in a certain slot, it stays there until fired or it dies.
At the start of every day, the game goes thru a certain process for the recruitment (for agents, scientists, engineers):
a) check the previous day's available recruits. If they remain hirable, leave them in current slot, otherwise remove them.
b) Roll to see if any HUMAN agents appear. If so, generate them into the first available slots in the list.
c) Roll for biochemists. Then engineers. Then Astrophysics. And fill the first available slots. In that order.
d) Ditto for Hybrids, then androids.
Any units that are fired or die will free up their respective slots, but these slots will only be available to be filled up when the process starts over again the next day.