"That one link in the instructions" http://scratchtale.orgfree.com/items.html README! Project might take a while to load. That's because there is a ton of music inside. A skeleTON. Making Undertale battles was never easier! Follow on-screen instructions to create your own battle in less than 30 minutes (if you are fast enough?) After creating your battle, simply click "remix" to save it!
credit to pococikapusta for the maker of the battle creator edit 1: lowered enemy HP by 80% (from 12500 to 2500)