Look at this new graphic design technique I learned! This is like 900% cool!!!
The file provided for the challenge appeared to be the flag, as you can just make out the start of the word flag, but the rest is swirled to make it unreadable.
I loaded the image in GIMP (GNU Image Manipulation Program) and used the “Wirl and Pinch” tool found under the Filters->Distorts toolbar menu. Adjusting the Wirl, Pinch and Radius sliders was a tedious process of slowly changing one slider value, observing how it affected the the others and how the image looked… over, and over, and over again… Eventually I produced an image that was clear enough to read the flag. Admittedly, this is where I kicked myself because I realized I missed a HUGE clue in the challenge description that would have saved me a ton of time. The clue was: This is like 900% cool!!!. Leaving the sliders at their default values and only adjusting Wirl to -900% produces a clear image.