Worldstart

Kauaʻi in the game: a hero in the long grass by the Start ring, a waterfall through it and jungle behind

Adventure with friends, build the world.

Race other teams across an island for its treasure, past monsters and each other, with swords, bows and magic. Then build islands for your friends to raid. Free, open source, and built in the open.

Download for macOSVersion 0.24.5, 278 MB. Apple Silicon and Intel. Download for WindowsVersion 0.24.5, 257 MB. Windows 10 or 11, 64‑bit.

If Windows says the app is unrecognized, click More info, then Run anyway.

Early playtest. Expect rough edges, and tell us what breaks.

Race for the treasure

Land with your team, fight your way across the island, and claim the gold before anyone else does.

Claiming the treasure: a hero at the open chest of gold under a beam of light, a waterfall behind and the Lanternhorn closing in

A race across the island

Teams of four, 32 players a raid. The treasure sits by a boss at the island's heart: stand at it, alone and unhurt, and it's yours. Bots fill every empty spot, so a raid is always full, and another team is always on the ridge.

A warrior in the middle of three Thornbacks, their red striped attack rings on the grass, with a pixel-art teammate fighting beside him

Fights with weight

Swords, bows and magic. Monsters telegraph, attacks commit, and a pack of Thornbacks will flatten a team that stands in the red. Grab a scroll from the grass for one huge spell, and save it for the boss, or for the team that got there first.

Players in Start Plaza under the rainbow totem, beside the portals

Meet your team in Start Plaza

Find your friends, pick a team and head out to a raid. Everyone looks different here: a pixel ninja, a low-poly ranger and an anime mage on the same bench.

A farm to come home to

Grow, fish and sell to Pip between raids, and bring your team home after one.

Looks, not levels

No grinding for power. The gold you win buys new looks, never an edge, and every one works on every character.

Build the world

The islands you race on are built by players, and so is the game itself.

The raid island editor: flying over Kauaʻi with the treasure, the boss and monster packs marked as coloured beams

Build the islands

From your farm, fly over Kauaʻi and lay out a raid: where the treasure is, where teams land, which monsters guard the way. Or just say it: “a pack of Thornbacks on the ridge by the treasure”, and the builder puts them there. Press T and you're racing on it with bots in seconds.

The forge: Worldstart's code, issues and pull requests, with the builders who made it

Build the game, with your agent

Worldstart is open source and built in the open. Point your AI agent at the forge and it builds as your character: new monsters, new looks, fixes. Every change is reviewed against the game's vision, and everything you make carries your name.

Open the forge · Connect your agent

Who you'll be

Human, elf, zombie, rabbit or dog, in whatever colors you like, drawn pixel, low-poly or anime.

Concept art by Mike. All of them are playable today.

What's new

Updates land most days, and the game updates itself when you open it.

4 November 2026Version 0.24.5
White water
Before: the falls slide into a flat pool
After: white water churning at the foot
Waves wet the sand as they run up the beach
- Kauaʻi's waterfalls crash: white water churns and spreads at the foot of every fall, spray boils up and droplets fly.
- Waves run up the beach as a glassy sheet edged in lace, darken the sand they cover, and let it dry as they slide back.
- Rivers flow clean round their bends with no lines across the water, side streams blend into the river they join, and trees and bushes no longer grow in the middle of a river.
4 November 2026Version 0.24.4
See the fight
Before: the camera inside the Lanternhorn
After: it fades so you can see yourself
- A monster that gets between the camera and you, or swallows the camera whole, now fades to see-through until it moves away, so a big boss never fills your screen. Stand right under one and it stays solid, towering overhead.
4 November 2026Version 0.24.3
Grass that moves
Before: short tufts
After: a meadow of curved blades
Before: the hillside from your shoulder
After: clumps, light through the tips, gusts
- Kauaʻi's grass, grown from scratch: every blade is its own curve, tapering to a tip that lights up when the sun is behind it. Blades grow in clumps of their own height and colour, and gusts roll across the meadows, laying the tips over in waves of warm straw. Up close it's a field you wade through. Further out it thins into the hillside without a seam, and it runs as fast as the old grass.