i really need rotation/mirror in the sprite creator it would make life a lot easier than it is now
In the meantime, you can download a Sprite, flip it, and re-upload it. The Sprite editor is not specifically designed to be the only thing you used, it’s more designed to make quick fixes or quick Sprites, without having to use gimp, Photoshop, whatever it is that you actually should use, something with significantly more tools. Flowlab is intended to be a game engine, not an image processing creation program. I agree that flip should be added, but don’t expect it to be added, in case it doesn’t.