Hello,
Here is my entry to the sketch #15. It is an explosion inspired by the VFX from the game Smash Bros Ultimate.
For my version I decided to fade the smoke differently, creating some ball shades as it was shrinking in the air. I also changed the timing of the shockwave, as the reference plays it at the first frame, I decided to play it after the anticipation, as I thought it would be better out of a fighting game context.
I am also open for feedbacks and suggestions 
Love the colors that you chose. It’s looking good!
Great anticipation to the explosion! If you have the time I would like to see more process work!
I love the use of the initial black frame. Less so of the black streaks that linger after the shockwave. They feel like they overstay their welcome.
You got some bad luck with your particles lining up in roughly the same rotation and lifetime. Using an atlas of 4 similar explosion shapes, and randomly mirroring the x scale / UV can help a lot to add some randomness to avoid that.
The texture ends with ~5 spots that all fade out in unison. I would try to modify the texture slightly to try to get some to fade out completely earlier than others. A few well placed dabs of a soft 5% fill brush on the peaks can do wonders to make the fade out timing feel more natural.