They Are Billions: Defend a Colony of Survivors Against Billions of Infected Zombies

They Are Billions is a real-time strategy game with survival elements, set in a grim, dieselpunk post-apocalyptic world overrun by zombies. Tasked with building and defending a colony of the last human survivors, players must carefully manage resources, expand territory, and fortify against swarms of infected that can number in the tens of thousands. A single breach can spiral into a total collapse, making every choice critical and every moment tense.

Plot and Setting

The game is set in a world where civilisation has fallen due to a catastrophic zombie outbreak, leaving only pockets of humanity struggling to survive. Most of the world has been lost to the infected, and players take on the role of a colonial commander, working to reclaim territory and rebuild against impossible odds.

In Campaign Mode, players follow a loose narrative of a fledgling empire seeking to re-establish order by building colonies across the infected wilds. The campaign explores humanity’s desperation, ambition, and hubris in the face of extinction through missions, technologies, and story cutscenes.

The setting mixes steampunk aesthetics with grim survivalist architecture—massive gears, brass fixtures, windmills, and turrets all dot the harsh, overgrown landscapes of a ruined Earth.

Gameplay Mechanics

Survival RTS with Pause:
- Played in real-time, but with a tactical pause feature that allows players to issue commands and plan carefully.
- Players must build up colonies, manage population, gather essential resources (wood, stone, iron, oil), and construct defences.
- The challenge is amplified by tight space, limited time, and deadly stakes.
Base Building and Resource Management:
- The core loop involves constructing housing, food production, energy generators, lumber mills, mines, and workshops.
- Each building creates noise and draws attention—over-expansion can lead to sudden death if not properly defended.
- Buildings are interconnected—power, workers, and resources must be balanced delicately.
Massive Zombie Hordes:
- The infected are slow and dumb initially, but they grow in density, aggression, and scale as time passes.
- Hordes come in waves, culminating in an apocalyptic final assault where tens of thousands of zombies attack from all directions.
- A single infected individual breaching your population can lead to an unstoppable cascade as infected civilians multiply exponentially.
Troop Management & Tech Tree:
- Players can train units like Rangers, Soldiers, Snipers, and Titans, each with unique roles.
- Later upgrades unlock powerful defences like shock towers, ballistae, and advanced bunkers.
- Tech development adds complexity—researching new units, structures, and enhancements through workshops and engineering centres.
Campaign vs. Survival Mode:
- Survival Mode is the classic roguelike experience: randomised maps, permadeath, and high replayability.
- Campaign Mode introduces story elements, permanent upgrades, and hero missions with smaller-scale RTS-skirmish gameplay.

Themes

Survival Through Sacrifice: You will lose colonies, troops, and time. Victory demands harsh decisions and sometimes abandoning your people.
Scale and Dread: The title isn’t an exaggeration—you are fighting billions of enemies.
Humanity vs. Nature: Civilisation claws its way back through fire, automation, and steel, but the natural world is corrupted and unrelenting.
Preparation is Everything: The game rewards planning, foresight, and defensive ingenuity—a reactive playstyle is often punished harshly.

Visuals and Audio

They Are Billions is viewed from an isometric perspective, with detailed sprite-based graphics that offer a clear, crisp battlefield view. The environments evoke a mix of frontier hardship and steampunk futurism, with mechanical buildings bristling with pipes and wind-powered gears rising from zombie-infested forests and wastelands.

The most striking visual moments come when waves of thousands of infected crash against walls like a grotesque tide—AI optimisation and visual clarity keep performance smooth even with overwhelming on-screen enemy counts.

The soundtrack is tense, ambient, and industrial, designed to enhance the atmosphere of creeping dread. Alarms, unit callouts, and the roar of gunfire create a sharp sense of urgency during attacks. Audio cues are critical; you’ll hear the first breach before you see it.

Have you played They Are Billions? What’s your favourite part of it? We’d love to hear from you.

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