I'm confused as to what you're saying. I don't get how you're coming up with 20 downs..?
The first time I did downs, I only needed 3 to avoid 100% loss. The second time I did it, I only needed 6. The third (and last) time I did it, I only needed 9. Each time, I was able to get enough downs to reach stage III before my three days were up. Plus, I can still do all the downs with specific weapons. As for executions, I needed 2 the first time and 4 the second time, and again, I was well beyond stage III both times.
I'm not trying to build my clan to high numbers or anything... I just want to finish the mode so as long as I avoid 100% loss and have 1 guy left. I just finished the Hunter one and started the Firefly one (and unfortunately, I won't get to play for a few days because we lost our internet... using a tethered connection right now, which can't be used for gaming).

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