This is ancient, from the Scratch 1.4 days. But it still works. I could probably do the same thing in Scratch 2.0 by editing the JSON file. (comment for info on that) V all that below is outdated V
Okay... you know as well as I do that variables and other values can only have one watcher, right? And that only variable watchers can have sliders, right? Wrong! Technically, yes, but that doesn't mean it's impossible. Here is a project that has both. To do this, use the scissors to delete a watcher from the stage, go to its appropriate scripts tab, click the check box for it, and hit edit, then undelete. Finally, I hacked Scratch's code to let you right-click on non-variable watchers and turn them into sliders. To get the sprite to have no costumes, just delete all but one costume of a sprite, hit, "Paint New Costume", drag the paint editor aside, delete the costume that is not blank, and hit, "Cancel" on the paint editor. Just make sure that the looks tab is not selected when you do this, and don't go there after doing this, or else a red debugger comes up. If this happens, hit, "Abandon".
