How to Play Level 13 - Step by Step
The Level 13 page loads a ~8 MB text-based survival incremental in an iframe. Explore a ruined underground City sector by sector, scavenge resources, build a camp, and unlock a tech tree - everything is click-driven. Press Play to start.
Step 1 - press Play on this page
Press Play to inject the iframe (~8 MB: engine, audio, and images, downloaded once and cached). Level 13 is an open-source Apache-2.0 game by nroutasuo; its own in-app credits and changelog ship unchanged.
Step 2 - explore sector by sector
Each new game generates a unique underground map from a random seed. Click your way from sector to sector, scavenging resources while radiation, hostile scouts, hunger, and cold work against you.
Step 3 - build up your camp
Spend scavenged resources on camp buildings - workshops, greenhouses, hospitals - as you find the blueprints that unlock them. The tech tree compounds the longer a single run goes.
Step 4 - let it autosave
Progress autosaves in this browser roughly every 2 minutes, and a manual save option is also available. Multiple save slots let you keep more than one run going side by side.
Step 5 - come back later
There is no account and no server - the save lives only in this browser's site data, so clearing it erases the run. Close the tab any time; your last autosave picks up where you left off.
| Setting | Value | Notes |
|---|---|---|
| Download | ~8 MB | Same-origin iframe; cached after first load |
| Input | Click/tap only | No keyboard shortcuts, no gamepad |
| World | Seed-based, procedurally generated | A new seed each new game |
| Saves | Autosave ~every 2 min + manual save | Multiple slots; stored only in this browser |
| Network | None after first load | Upstream visitor counter and error tracker removed for this hosting |
See when to play, comparisons, and Space Huggers.
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