NK Coins (Ninja Kiwi Coins) is the currency used by Ninja Kiwi that you purchase with real-world money or earn by doing tasks. They are used in Ninja Kiwi games to purchase premium upgrades, or simply more in-game currency. They are used in Bloons TD Battles to buy Medallions and to increase Battle Energy, used in Bloons TD 4 and Bloons TD 5 to purchase upgrades such as Healthy Bananas, or in Bloons Monkey City to purchase premium buildings.
The exchange for NK coins is as following. Keep in mind this is up to date as of April 26th, 2012. This info was also taken right out of the Ninja Kiwi Buy Coins page. Note that the following is costing in US Dollars.
- $5.00 = 50
- $10.00 = 105 (+5%)
- $20.00 = 220 (+10%)
- $50.00 = 575 (+15%)
- $100.00 = 1,200 (+20%)
- $200.00 = 2,500 (+25%)
As of March 21st, 2014, users are no longer able to earn free NK Coins (except through the wheel of fate) after admins shut it down due to a mishap, scam, viruses, phishing, and as well as an odd complaint that has occurred. The wheel of fate(aka the level spin) gives between 10 and120.