In a way, a gauntlet is rather similar to a treasure hunt.
You get a theme or subject from the person who prepared the gauntlet, and then you go through a series of steps.
On each step, you're presented with up to three pictures, related in some way to the theme or subject of the gauntlet. You have to figure out how those pictures are related to the theme, and write down what they intend to describe.
You're given a text input, which will tell you how many words the answer has, and how many letters each of those words has.
If you get the description right, you advance to the next step, and are presented a new challenge. If you get the last level right, you advance to the last screen, with some sort of success message.
To try it out, try out this demo. The answers will be 'whitesmith', 'pedro janeiro' and 'gengar'. Don't ask.
Have fun.