Backstory: One day, griffpatch and his cat were taking a walk. A mean scratcher pushed his cat into a safe. You need to escape! Instructions: Arrow keys/WASD to move. Down key or S to crouch. Avoid things that look bad [i.e. -1 coins, blobs etc.]. S or down arrow to drop down fall-through platforms (crates). Also, J key to save your level (in editor mode). P key to load a level code (in editor mode). M key to toggle music. Q+N keys to toggle editor. L key to switch levels. R key to reset a level. Q+F keys to toggle auto-arranging tiles. 1-0 keys for different things for your level. The rest of the instructions are found on the main page.
Thanks to @griffpatch for his Tile Scrolling Platformer Tutorial on YouTube, the cat, and the player death particle idea.