Today the game has given us a new challenge: the Underwear Thief
He first appears in Humpreydale. There are 5 challenges to complete.
First challenge is 5 time missions
Second challenge is 5 duels won
Third challenge was refreshing second hand shop 3 times
Fourth challenge collecting 10 suspicious laundry items. (These are mission items in the form of underpants.)
The fifth challenge isn't really a challenge. You just click through it.
After Humpreydale is complete, the Underwear Thief runs off to Dirty Downtown.
The first challenge there is completing 50 duels.
That's where I am now, so I have no more info.