When you go to the level editor from the main menu, you will be presented with a list of the levels you are currently creating on your local computer, as well as the option to create a new level. From here, you can select an existing level and proceed to edit it by hitting the Play button, or you can choose to delete it with the X button.


You can create a new level with the New Level item at the the beginning of the list. If you choose to create a new level, you will be taken to the main level editor and asked to enter a name for your level. In order to test and upload your level to the Steam Workshop, you must have a name. Names are limited to 32 ASCII characters.


In order to upload your new level to the Steam Workshop, you must solve the level.

The level editor lets you create levels for Unium. You can access it via the level list described in the previous section.


In the editor, you may click on any tile cycle through the available colors. Tiles start white, then cycle to black, then gray, and back to white again. Your level must have at least one black tile in it in order to test.


You can change the size of the level grid you are using with the arrow buttons at the top of the level editor screen. The level grid will always expand and contract from the top left corner. If you have any non-white tiles at the bottom or right edge of the grid when you contract the size, those tiles will be lost.

You can reset the entire level grid to white with the X button at the top of the level editor screen. You will be prompted to confirm before this action is executed.

You can change the name of your level using the settings button at the top of the level editor screen, next to the reset button.

The play button at the far right of the top of the level editor screen will take you to a special testing mode where you can determine how your level plays. Note that in order to enter this testing mode, you must have a name for your level, and you must have at least one black tile in your level.

You can only upload your level to the Steam Workshop once you have solved it.

In order to submit your level to the Steam Workshop, you must first test it and find a solution to it. You can do this in the testing area, which is accessed from the level editor. See the previous section for more information on accessing the testing area.

Note that it is very possible to create an unsolvable level, so try to keep solutions in mind when creating your layout so you can be confident it's possible upon entering test mode. But if you can't solve your level, return to the level editor and make some changes, then try again.


After you have solved your level, you have the option to submit it to the Steam Workshop.


After you have submitted your level, you will be given a web link to the level's Steam Workshop page. As long as you are logged in to the web browser with your Steam account, you can edit descriptions for your level. Note that you must agree to the Steam Workshop agreement in order to have your new level be publicly visible.

Any levels you have subscribed to will be available to play in the Custom difficulty. Note that if you subscribe to a level while Unium is running, you must restart Unium before the level will be available to play.


Besides levels you have subscribed to, any levels that you are currently creating on your local computer can be played here, as long as they have been solved. If you solve a level, then modify it, you will need to solve it again in the testing area before it will show up in the Custom difficulty level list.