Someone asked me to make a level editor, so here it is. Enjoy :) Music is "Menu BGM 2", by guyperson42x on NG.
Guide to the level editor: The "Build" tab is where all the objects are stored. Click an object, and you will select it. Once you have an object selected, just click anywhere in the level preview to place it there. The square platform is exactly what it sounds like. You can stand on it, wall-jump on the side, and bump your head on the bottom. The spike is dangerous. Touching any side of it will cause you to die and be sent back to the beginning of the level. The bounce pad launches you in the air, at a height that is about 2 times your regular jump height. You do not need to land on top of the pad to do this, just touching the side works all the same. Water blocks allow you to swim through them. By jumping while inside of one, you will go up at a slightly shorter height than that of your jump height. Gravity and wall jump height are unchanged. The goal is self explanatory. Touching it will complete the level. The "Edit" tab is where you can edit certain setting about the block you have selected. To see what you have changed, simply view the preview attached to your cursor. The rotate buttons rotate the object you have selected 90 degrees. This currently only affects the spike and bounce pad, as all other objects are squares. This will be updated if I add a new, non-square object, or if I add a more advanced rotate feature (45 degrees, 14 degrees, etc.) The size change buttons change the size of the object you have selected. The smallest you can make an object is size 1 (0.5x) and the largest is size 10 (2x). The "clear the level" button does exactly that: it clears the level you are building. This can't be undone, so use it wisely. The "save and play" button causes the toolbar and UI to disappear, and you can now control your character. Like clearing, this cannot be undone. Remixing the level in this state will allow you to upload the levels you make. That's about it. Happy creating :)