Civilization: Beyond Earth lets you decide the future of humanity. Will you respect the new planet you've colonised, or suck its resources dry to build bigger cities and better war machines? The affinities system is a powerful expression of those choices that affects your civ's path, from its technological focus to the way your cities appear on the map.

There are three affinities in Civilization: Beyond Earth: Purity, Harmony and Supremacy. According to co-lead designer, David McDonough, "They influence not just the way things look, but the way that they move, and the way that they build. The three identities are the combination of who humanity is when they land on the planet, and what they find, and how those two collide for the next two thousand years."

You side with an affinity by unlocking affinity points. These are scattered throughout the tech web, attached to techs that align with the philosophy of the affinity you're pursuing—expect lots of alien biology research to grant you Harmony points, for example. As you expand across the surface of the new planet, you'll encounter quests, which can offer affinity rewards depending on your choices.

It is possible to amass points in conflicting affinities, but over the course of the game, your choices will push you towards one more than the others. That's when things get really interesting. Let's take a more detailed look at each of the three affinities, and the values they represent.

Harmony

"Harmony finds that the planet is a beautiful place," David McDonough explains. "It's a gem, a jewel. Maybe the mistakes that they made on Earth, pillaging, polluting and so on, they don't want to repeat, so they find a way to make themselves belong on the planet."

As the name suggests, the Harmony path focuses on learning to live with the indigenous creatures on the plant you've settled. Harmony citizens learn from the ruined Earth they've left behind, and try to build cities that incorporate the systems they see in alien nature. This makes them a fast and flexible civ. They can learn to utilise the lingering miasma that poisons other factions, and can build units that weaponise the planet's most dangerous creatures.

"The Harmony player can take advantage of all the things that are threatening to you in the beginning of the game," co-lead designer Will Miller explains, "even to the extent that they start to design their own alien creatures. You get to play these big alien things at the end of the game, they even ride them. "They're not space elves, they're still very tough. In fact, the ground unit trajectory for Harmony, they look like Football players, huge genetically modified guys."

As you adopt an affinity over the course of many turns, you'll start to see your cities and units change. Harmony architecture is smooth and organic, replicating the aesthetics of alien fauna. Each affinity also has its own victory condition. The Harmony player unravels the mystery of the planet and communes with its collective consciousness to achieve a state of transcendence.

Purity

Do you like huge levitating battle tanks? If so, the Purity affinity is for you. The Purity civilization can only see the new planet as a corrupting alien force that must be held back with high walls and turrets. Humanity must be preserved in its current form, and grow strong in spite of any indigenous critters who might try to tear their cities down.

"It's a very plausible philosophy of what humanity would do if faced with, as the quote goes, 'the unimaginable strangeness’ of space," says David McDonough, "which is that they'll hold on very tightly to what they know, and what they recognise, and where they came from."

This attitude is expressed most obviously in their military hardware. "I was never a fan of Batman, Superman, I like the Hulk. You don't need fancy tricks and gadgets, you just need to hit things really, really hard. That's the Purity attitude—overwhelming force." The Purity player exploits special resources to create levitation fields that let their vehicles hover above the planet's surface—perfect for creating battle platforms.

A purity civ will look rugged and resilient. Expect robust, blocky white architecture that stands in stark contrast to the strange, colourful fungus that naturally grows on the planet's surface. The Purity civ's love of Earth is reflected in their affinity-specific victory condition. You can build a portal back to Earth, and bring the humans you left behind to the new world.

Supremacy

If you love extraordinary futuristic technology, you'll find lots of interesting ideas on the Supremacy path. Supremacy civs don't necessarily care about the wellbeing of the planet, but unlike Purity civilizations, they're more than happy to tinker with the human form. They don't want to preserve humanity, they want to accelerate its evolution using spectacular new inventions.

"The Supremacy player says, ‘Well, technology is the salvation of humankind. The ability to build a colony ship is what got us off that world, we've got to keep going down that road, it's the only way we'll be safe and keep humankind going,’" says Will Miller.

On the tech web, Supremacy points are tied to transhuman inventions. Supremacy civs love bionic enhancement and robotics. Their units and cities look dark, sleek and dangerous. In Civilization: Beyond Earth, faction leaders will even change appearance as each civ picks an affinity. Supremacy leaders are adorned with glittering, borg-like skull apparatus. They're a little sinister, but extremely capable.

Militarily, you'll need to take a tactical approach if you want to get the best out of your Supremacy units. Will Miller: "The Supremacy player is very finesse oriented. It's going to be about building units and putting them in a geometry that lets them harmonise with each other. You have units that are very specialised, but if put in the right places relative to others, you get a lot of buffs that way."

Supremacy units use advanced cloud computing to improve their ability on the battlefield. The more processors they can throw at a problem, the more effective they are. That's why Supremacy units excel when placed adjacent to one another on Beyond Earth's hexes. If you keep your formations tight, it's going to be extremely difficult for other civs to break through your lines.

That's our quick look at Civilization: Beyond Earth's affinity system. It's a completely new aspect of Civ that will give long term fans of the series a lot of new strategies to consider. It also puts narrative in your hands. When you pursue an affinity, you decide humanity's role in the universe, so choose well. No pressure.