Galaxy Forge - Save, Scenario & Map Editor [4.5, 4.x]

Important: subscribing does not install the editor. This page has no mod files. It's here so people can find Galaxy Forge.

Galaxy Forge is a desktop editor for Stellaris galaxy maps, compatible with Stellaris 3.4 and later. It runs outside the game and lets you edit both existing save files and galaxy scenarios.

You can move star systems, draw and cut hyperlanes, and add new systems to an ongoing campaign. Inside a system you can rearrange its orbits, add and delete planets, and edit each planet's class, deposits and colony. You can also turn a save into a scenario and start a new game from it with the Paint a Galaxy mod.

Download: GitHub releases Builds for Windows, macOS, and Linux. The Windows installer is signed, but because the certificate is new, SmartScreen may still show a warning. Click More info, then Run anyway. The macOS build is not signed. User guide: how to use every part of the editor Source & bug tracker: GitHub

Editing a save

Open a .sav file, make your changes, save it, and load it in Stellaris to continue the same campaign.

• Move systems: Drag a star system to a new location. Its hyperlanes move with it and their lengths are updated.

• Edit hyperlanes: Draw new lanes, cut existing ones, or disconnect a system completely. The Connect and Cut brushes let you work in broad strokes. Join reconnects separate parts of the galaxy.

• Add systems: Right-click empty space to add a new star system. The Special entry adds unique systems such as Zevox. Systems you added can be deleted again.

• Change stars: Change a star's type or size, or apply a star class to a selection of systems.

• Edit nebulae: Add, move, resize, and rename nebulae.

• Edit wormholes: Link two systems as a wormhole pair, or unlink a pair.

• Edit empires: Rename an empire and change its flag. On a 4.5 save, also change its border and fill colours.

• Edit the L-Gate outcome: See which outcome the save rolled and change it until a gate opens.

The system view and planets

Double-click a system to open the system view.

• Drag planets, moons and belts to new orbits, and give a planet a ring or take it away.

• Add planets and moons, or delete them. A new planet gets its size and deposits from the game's rules.

• Cut planets and paste them into another system. They take their moons and stations with them.

• Drag a natural wormhole to move it.

Every planet and moon has its own page. Rename it, change its size, class or skin, and add or remove deposits, blockers, modifiers, anomalies and dig sites. You can also delete a colony without deleting the planet. The page warns you first when the game will take something away for an edit.

Making a galaxy for a new game

A scenario is a galaxy map that a new game starts from instead of generating a random galaxy.

Galaxy Forge can create a scenario from a blank map or from an existing save, keeping its layout, names, and fallen empires. The original save is left unchanged.

Systems, hyperlanes, and nebulae work the same way as in a save. Scenarios also let you:

• Add systems by right-clicking.

• Choose what each system spawns in the initializer browser, which lists everything your installation and mods define and shows what each one places.

• Set spawn points and their weights, and mark hyperlanes that the game must never generate.

• Place fallen empire zones, marauder clans, and wormhole pairs.

• Set the counts offered on the new-game screen, such as the number of AI empires.

Painting & symmetry

The Paint brush scatters clusters of systems and connects them with hyperlanes at the size and density you choose. Erase removes them again.

With symmetry on, every system, hyperlane, and brush stroke is mirrored around the galaxy centre or repeated 2–8 times around it.

Playing your scenario

To play your map you need the Paint a Galaxy mod, plus the Reserved Spawns submod if your map reserves seats.

Stellaris has some limitations with hand-made galaxies, such as empires starting on the wrong homeworlds. Oatmeal Problem's Paint a Galaxy fixes these, and Galaxy Forge scenarios are built around it.

When your map is ready:

1. Use File → Save into the Paint a Galaxy mod.

2. Enable the mod in your Stellaris playset.

3. Start a new game. Your custom map will appear as a galaxy size.

Steam may replace the mod's folder when the mod updates, so keep another copy of your map somewhere safe.

You do not need Paint a Galaxy to edit a save file.

What you can see

Select a system to see its position, hyperlanes and their in-game lengths, bypasses, planets, fleets, flags, and initializer.

Press F to search for systems by name or by what they contain, such as "gaia" or "leviathan". Pin a search and its results stay highlighted on every save you open. The Layers menu shows and hides map layers.

In a scenario, the Scripts tab shows the events and effects that affect a system, with the file and line of each. It is a best guess.

Keeping your save safe

Galaxy Forge edits save files at the byte level, so only the parts you change are rewritten. Everything else, including data from mods or newer game versions, is copied as it was.

• Each save keeps a timestamped backup of the previous file, up to eight per file. The first is the file you opened.

• If Stellaris saves over the file while it is open in Galaxy Forge, the editor asks before overwriting it.

• Every edit can be undone, and the Changes tab keeps track of them.

• The Issues tab checks for problems before you save, such as a hyperlane that exists at only one end.

Mods

Galaxy Forge reads definitions, names, and artwork from your installation and enabled mods, so modded systems show up and new systems can use modded content too. Nothing from the game is bundled.

Limits

Galaxy Forge is still in beta. Fleets, pops, leaders and techs can't be changed.

Galaxy Forge works with Stellaris 4.x saves, tested in-game with all DLC. The galaxy map edits are tested on 4.4.6 and 4.5, the system view, planet, empire and wormhole edits on 4.5 only. Hyperlane editing also works on saves from 3.4 through 3.9. I haven't tested Ironman saves.

Steam Cloud can restore the original save over your edited copy. Close Steam or disable Steam Cloud for Stellaris before playing an edited save.

Scenario editing is newer than save editing and has had less testing.

Bugs & requests

If you find a bug or want to request something, open an issue on GitHub. No GitHub account? Leave a comment on this page instead.

If you can, attach the save or scenario file. That makes the problem much easier to reproduce.