ADMIN: Surprise! Challenge

[dsudis]

In keeping with what is becoming a modly tradition of surprising you with mobile challenge deadlines, it's time for the Surprise! Challenge. Whether it's a surprise party, a surprising case development, or a surprise pairing, let's have some fun with the element of surprise!

The challenge will run for two weeks, until Thursday, September 13.

Suggestions for future challenges are welcome in the comments!