World Engines
Worlds, made playable.
A World Engine is a fully realized fictional world —
made playable.
Make a character, walk the world, speak with the people in it —
and live a story that is truly your own.
Nothing resets.
Nothing forgets.
Earn someone’s loyalty, and they remember it.
If something dies — it stays dead.
Lore-accurate · infinite branching · every choice carries weight.
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Narrator, game-master,
and author — in one.
It drives the story, tracks your condition and every relationship,
remembers each choice, and holds the world to its own rules.
World Engine · Live · Free
☣ RE: Rebirth
A never-ending, Umbrella-engineered simulation of the Raccoon City incident. Survive the outbreak, die, and wake to do it all again — the loop slowly fraying everyone caught in it.
World Engine · Live · Free
☢ The Windy Wasteland
A post-apocalyptic World Engine in the irradiated ruins of Chicago. Vaults, the Brotherhood of Steel, ghouls, raiders, and rolling rad-storms. Build your survivor and write your legend.
World Engine · Live · Free
☄︎ FFVII: Reclaimed
The Summons rise to reclaim a world once theirs — and wage war on the Weapons. The world of Final Fantasy VII, reforged into a living space you can step inside.
More worlds on the way
☽ SoonThe Afflicted
⚓︎ SoonTempestsea
✦ SoonAYEI
≈ SoonWhere the Wind Lives
Every World Engine is built
for one universe.
Its interface, atmosphere, and systems — themed from the ground up. No two are alike.
Play F.C. Marrow’s worlds free — or commission your own.
How it works
01
Build
Shape your character and bring your own lore. The world is already built — you decide who you are in it.
02
Inhabit
Step inside and drive the story. The narrator reacts, the cast remembers, the world holds to its rules.
03
Live It
Every choice has weight. No two playthroughs are the same. The story is yours alone.
World Engines
Step into a world.
Or build your own.
marrowmyth.com/world-engines.html
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