The game can be played with micro amounts, so if you want to try it you can use NANO from any of the faucets. Here's a site reviewing the available NANO faucets. Simply trying the game would have addressed all of the questions raised here.

http://www.tokenclaimer.pw/2019/05/get-free-nano-xrb-huge-list-of-nano.html

As many of you already know, NANO is a fast and feeless crypto. There are 30 decimal places of precision built into the currency. Currently most wallets allow up to 6 decimal places of precision. This means you can play the game with only one one-millionth of a NANO. This is less than one one-millionth of a USD. Again, there's no risk here. You can simply claim NANO from a faucet, put it in your wallet and try the game with this minimum amount.