Forfeited this one, I felt like I squeezed every ounce of performance out of my python solution that I could. Turns out I was getting through about 2/3 of the test cases. The other solutions I saw were heiroglyphs... very frustrating kata and I learned extremely little.

500 char limit doesn't spark creativity, it is a serious constraint and significantly increases the difficulty. Please consider updating the text to reflect this as this is not at all clear.

The setup for this Kata in JS is ridiculously terse. A simple function that accepts two arguments (hand1, hand2) would have sufficed as a starting point. There is absolutley no need to prototype.

This is by far the most efficient solution I've seen in JS. This algorithm can solve a 100x100 spiral in ~0.5ms. Other solutions I've tested hover around 10-15ms range; this one blows those away.