Best played in fullscreen! Left and right arrow keys to walk; hold Z to jump (or double jump). There isn't a goal; just jump around and have a look at the place. To access the editor, click the "Edit" button on the bottom-left of the stage. Press S to save the level if you want to make a remix.
Just a progress update! Here's a WIP editor for my Hollow Knight-inspired game. There are still a few bugs that need to be worked out, and most certainly some usability things that seriously have to be figured out (how do you select things in far-back layers..? does making each costume a rectangle make sense, or is there some better way..?). Plus there are lots of things like multiple-level UI and doors and what-not. But hey, here's what I've got so far! :P Credits to Team Cherry for Hollow Knight, which this project is based on all around, and of course which the player character sprite is based on (plus most sounds are from Hollow Knight). Also credits to Submachine, which inspired the art style a good amount here.