Absolutely brilliant sequel
This is without a doubt the greatest thing you guys have ever done. I didn't think it was even physically possible to top the first one, but this one easily surpasses it.
I liked how you explored the Running Man's family, and how they reacted to his death. The dialogue was well written, and funny as well. The way the children dealt with the loss of their dad, and the whole build up to his son gaining his running powers was really great.
The end was especially awesome, and the son's decision was definitely not what I expected. Then you even manage to make what is probably the funniest credits sequence I've ever seen, and having Morgan Freeman star in it was hilarious.
And finally, the sequel hook at the end played out perfectly. My guess is that it will explore the other side of the short, the one the audience didn't get to see.
So all in all, this is a satisfying and magnificent follow up to the first one, and I hope to see the next part soon.