adding a puzzle option on create a giveaway

It would be cool if you could make a puzzle giveaway but on create a giveaway.

here is what it should do:

instead of posting on forums and stuff we could chosse to make it directly on the giveaway. Instead of finding a hidden link the giveaway page unlocks and the one that solved it can enter.

what do you think ? Would it be good or bad? Feedback maybe? Is it unclear?