Board Thread:Game Discussions/@comment-198.255.133.71-20141010005453/@comment-69.243.101.174-20141013163630

Costs about 300 gems along with constant 5x play to get in the top 100. Top 10 is at least 2500 gems so top 3 would depend on how much competition you had but I would guess at least 4000 gems at the minimum.