You can draw your own custom maps, freehand or with some basic drawing tools, and then drag and drop pre-made "[doodads](doodads.md)" into your level for interactive things like keys, doors and buttons.
Growing up in the era of 2D platformer games on the likes of the Sega Genesys and Super Nintendo, as a kid I would often draw my own levels with pen and paper and "play" them with my imagination. My mazes had all sorts of features borrowed from videogames I liked. There would be buttons that the player had to push that would open a door far across the level (and I'd draw a little dotted line showing the connection between the button and the door). Trapdoors would have the player fall through and then close behind them so they can't go back. Keys in different shapes could unlock doors in similar shapes (you'd just have to remember which keys you've got!)
When you're just drawing with a pen and paper, the level can be anything you want. You can draw a castle or a cave, place little gizmos and traps throughout the level (doors, keys, buttons and things) and create puzzles. Do you want the red pixels to mean "fire" and burn the player? Or do you want to decorate the tops of "bloody" spikes with red? Either way, the 'fire' attribute on that color will do the job and you can draw whatever shape you want for your level hazards.
While the game ships with a [handful of built-in doodads](doodads.md) to spice up your level, you can also create your own and program them to do whatever you want, [with JavaScript](custom-doodads/scripts.md)!
The game also has a few "generic" scripts built in that you can choose from, to create your own simple doodads with no programming required! In the future, template doodads can be created to be able to draw custom player characters, Warp Doors and other complex doodads with a script already attached.
Full versions of the game let you bundle custom doodads _inside_ of your custom levels for easy sharing to other players. Custom wallpaper images embed in a level file for all versions of the game.
