Rank Up Island

Rank Up Island is the highest island in the game, and the only one to not feature a reward of coins or gems. Instead, the island gives the player an opportunity to rank up, paying cash upfront and losing all items they bought with cash, as well as fuel. Fuel Bots and all gems + items bought with gems are kept. In return, the player is allowed to collect the other island rewards again and gains a multiplier (Rank Up Bonus) which multiplies the cash for each rocket they launch by a certain amount. For more details, see the Ranks page.