User blog comment:Robot746/New special mission ideas for BTD5!/@comment-202.150.1.24-20120617112005/@comment-202.150.1.25-20120617112330

Another cheat: Use 3 or 4 Villages and places many Super Monkeys around them. Sell all villages and Super Monkeys, you gain a profit.

Only works with Monkey Tycoon.

P.S. Ring of Bloontonium is an upgrade after Ring of Fire (P1U5 and Unlock at rank 66)