Sid Meier's Alpha Centauri
Platform: Windows, Mac
Easily one of the best 4X games ever developed, available at GOG now for only six bucks, if you haven't played it yet just stop reading and go buy it and you'll easily spend a couple hundred hours playing before you realize it.
Or, if you insist there is more to say in review.
Positioned as a sort of thematic or conceptual sequel to the starship victory in the Civilization series, Alpha Centuri follows the colonists to their new home where they promptly split into ideology driven, as opposed to nationalist or ethnic, factions and start competing for dominance.
It plays largely like other games in the Civilization family tree, the most obvious mechanical difference being that unlike most other Civ games you can design individual units rather than just getting a default unit with certain tech advances. But there is more to the difference than the obvious, some of the mechanics are significantly different from Civilization's model, and often better. Alpha Centauri has a dynamic weather system and you can use terraforming to not only help your own society but to hurt your enemies. Change rainfall patterns to make their crops wither, or even flood them via global warming. The tech tree is improved as well and has an option for blind research that adds an interesting element to the game.
But what sets Alpha Centauri apart from the Civilization series is not just setting or tone, or even the mechanical differences, but the fact that Alpha Centauri has a story and characters. The characters are developed mainly as you climb the tech tree or build wonders, each tech or wonder has a quote that is usually from one of the faction leaders and helps breathe life both into their faction and the leader themselves. The story develops as you play, both in alterations to gameplay and in small text vignettes.
The planet, simply called Planet, is inhabited by life that's alien beyond even starfish aliens. The dominant life form is a fungus, simply called xenofungus or "the fungus", and all the other life you encounter is deeply related to and basically part of the fungus. The fungus is also telepathic and pre-sapient when you first encounter it, but grows into a person, a single mind, as it spreads over the planet.
At first the fungus is an obstruction, worthless in terms of resources, slowing down your units, and acting as a hiding place for mind worms which are exactly as awful as they sound; the discovery of fungicidal add ons for your terraformers seems like the best thing ever. As you progress you can learn how to make the fungus the most valuable resource in the game, you'll be carpeting your territory with as much as you can manage and you'll curse your earlier efforts to get rid of it.
Alpha Centauri takes a decidedly transhumanist approach to things, allowing cybernetics, genetic engineering, brain mapping and upload, and more. All of which fits the game perfectly and helps propel the story to its natural conclusion.
Each faction is clear, has advantages and disadvantages that fit its ideology, an agenda that makes sense given that ideology, and they will react to you based on your social decisions as well as your more overt diplomatic or warmaking decisions. The AI isn't especially amazing, but it does a good enough job of providing a challenge.
In addition to the quality writing for the factions and the storyline in general, Alpha Centauri features well done voice acting for each faction leader that helps make them memorable. The rich rolling voice of CEO Nwabudike Morgan helps establish him as the sort of person who despises most of humanity but makes a pretense of caring about the little people, while Sister Miriam Godwinson speaks with a subtle (and sometimes not so subtle), but threatening, air of conviction and righteousness.
If it weren't for the overarching story, the rich world building, the well developed factions, and the integration of transhumanist themes, Alpha Centauri would simply have been Civilization with different art assets (looking at you Civilization: Beyond Earth) and we'd have long forgotten it. As it is, it stands out not merely as a well done member of the Civilization family, but also as one of the better 4X games yet developed. This shows that it is possible to incorporate a story and characters into the 4X genre, and that if done well it can make the game vastly better.
It holds up very well, both in terms of graphics and gameplay. Despite being 17 years old the gameplay is still fresh (which says something not at all hopeful about the 4X genre, which seems to be stagnating) and the game entertaining and challenging.
The only expansion for the game, Alien Crossfire, is a mixed bag. The alien factions are interesting enough, and obviously thought went into trying to make them alien, but the extra human factions mostly seemed cheap and lazy compared to the original factions, a couple stood out as worthwhile but mostly they were bleh. Mostly it is worthwhile for the gameplay improvements, the addition of fungal towers we very good, and some of the added tech improves the game greatly. Fortunately it is possible to use the improvements of the add on without bothering with the somewhat inferior factions it included.
The combination of a fresh take on the 4X genre, the well executed world building, the addition of personalities, characters, and story to the 4X genre, all combine to make Alpha Centauri a game truly worthy of an A.