Inspiration

Every alien-invasion story is told from the ground. We wanted the other seat: you are the saucer, the tractor beam is your only tool, and the world you are raiding is also your supply line. The twist that made it a game: the enemies chasing you are the ammunition you need to survive them.

What it does

UFOBIA is a single-player, portrait survival run across three tiny planets: a green world, an alien desert and an ice world. Fuel counts down from the moment you land. The beam is always on — there is no grab button: fly over an animal (shield), a uranium barrel (fuel), or a car, soldier or tank (boost and weapons) and it comes up. Only what you swallow pays coins and ammo; shooting just makes noise. Noise fills the planet's alarm, up to five stars, and when the last one fills its boss drops in next to you. Beat it, spend your coins on upgrade cards aboard the mothership, and fall onto the next planet with everything you are carrying. Lose your shield or run dry and the run ends.

How we built it

It is a self-contained Three.js / HTML5 build with no server, no accounts and no network calls. There are no imported meshes or textures: every 3D model is procedural, drawn in code with a cel-shaded, single-palette look, and the sound effects are synthesized at runtime, so the whole game fits in one ZIP. The game was prompt-built with AI coding agents (Anthropic Claude and OpenAI Codex) working inside the editor from plain-language descriptions, with every decision recorded in the build log. Balance came from real phone playtests, replayed and measured, not from guesses.

Challenges we ran into

Keeping one tight loop. We built more than we shipped: a fourth city planet, a second hand-made boss, the original cargo-and-trading loop, planet choice. Most of it was cut so a judge can understand and win the first planet in a few minutes. The last thing to go was the abduct button itself, days before submitting — holding it down for a whole run was just tiring, so now the beam is always on and flying over something is taking it. Mobile performance was the other fight: portrait phones, a full planet, dozens of enemies, and still smooth. Touch controls that never stick, audio that unlocks on the first tap, and a shop that fits a small screen all took real iteration.

What we learned

Feedback, rhythm and tension make people want one more run; content does not. The abduction feel (grab, resistance, tear, lift, swallow) carried the game more than any new system — and the change that helped most at the end was deleting a button, not adding a feature.

What's next

A harder roguelike meant to be replayed: procedurally generated planets so no run can be won from memory, more worlds, a wider set of abilities, and difficulty that climbs well past this prototype.