my contest idea

[harmor19]

I was thinking of having a contest on my site and I thought of this idea. Below the navbar will show underscores where letters should be. It'll work like Wheel of Fortune or hangman but instead of guessing the letters they have to post a certain amount of times to reveal one letter at a time.
If the word was "Greyhound" and the number of posts they had to make was five then for every five posts they'd see a letter. I want it to show the letters randomly but as I'm processing how I'd do it in my head I can't think of what to do.

Back to the contest idea... If user A posts 20 times he'll see "Grey_ _ _ _ _". If user B posts 10 times he'll see "Gr_ _ _ _ _ _ _". The first person to guess the word wins.