I like this kata, very enjoyfull and really looks like something real, like if you develop a game.

But there was a tricky thing, without knowing which I couldn't solve it. The key is that incomeng string includes not only dots "." and letters, but also "\n" symbols, that allow you to do tricks like arr.split('\n'), or find another solution.

I was confused because I thought that the strings had to contain only dots and letters.

To test different use cases in your code editor, you have to put map inside `` brackets, not standard "".