The contest rules say:
Each Achievement you unlock gets you one entry into a drawing for prizes. The number of names drawn will be equal to 25% of the total number entries.
There are 6 achievements, meaning than there are up to 6 n entries where n is the number of entrants. 25% of 6 is 1.25, meaning that there will be 1.25 n prizes for n people in the "worst" case. Is this intended? Are we banking on the hope that most entrants will not acquire all 6 achievements?
I am also hoping to clarify this bit of the rules:
25% of the people entered into each raffle will be selected. If you complete more than one of the Platinum, Diamond, and Master leagues, you'll be entered into multiple raffles, but you can only select one prize.
In the normal reading of this I'd think that "selected" means selected to win, which would mean that if someone wins multiple draws you have a bit of a complicated process to ensure that the 25% promise is met (discounting them from the other draws decreases the number of winners):
Wait for them to get back to you about the prize they want
Draw one more person from all the raffles they qualified for but did not select
Hope this didn't create any more multiple-winners, otherwise goto (1)
I'm guessing this isn't what you're going to do, so I'm just curious as to what the plan is!
And I apologize for thinking in edge cases; I'm a programmer.