Thank you for your explanation! Explanations are important too. I can tell there is a stop, but it might just have to do with the resolution of the image out of the program you exported it from, so that wouldn't be your fault if so. To make it look all black, you could open the GIF in GIMP and add black all over the last frame. There are some particles I see in the gif currently. So that is my advice on how you could do that! This is just my personal opinion though so take it with a grain of salt, I get the concept either way so its great for an hour's work!