Build a level like this...
And then watch it come to life!
The levels are saved externally with the extension .ygl... you'll be able to send your own custom-made levels to fellow Yellow Goo Love players and the like. I'd go as far as to say that this feature could be the game's killer app.
Though, I'm not actually going to let people get their hands on it until the game's finished. You need to beat 25 levels to unlock the custom level maker, and I don't plan to put out any more than the first 20 levels for now. After I clean up a few loose ends with the custom levels, I'll get back to level designing and hopefully will wrap up this game soon. It's been a surprisingly long process making this game, mostly because I've been working on it very infrequently.
Special thanks to Brod, who gave me the basic structure for the level maker and without whom it wouldn't have been possible for me to tackle.