The concept is clever, but I think the implementation is potentially tricky and might encourage undesired behavior. For example, how do you handle edits, does it only count if it's your original answer, no edits? Also, wouldn't this encourage simple, fast answers? Simple and fast answers are good and acceptable, but I don't think they need to be encouraged, which is the point of badges.

The concept is clever, but I think the implementation is potentially tricky and might encourage undesired behavior. For example, how do you handle edits, does it only count if it's your original answer, no edits? Also, wouldn't this encourage simple, fast answers? Simple and fast answers are good and acceptable, but I don't think they need to be encouraged, which is the point of badges.

EDIT: In response to your edit. I understand the intent is for quality answers, however, unless N was quite high I believe it would likely encourage behavior that shouldn't be encouraged.