Ready for another insanely complicated challenge? One of the coins you see here is special. The other 63 are useless, except that they collectively instruct you to the location of the special coin, if you know what you are looking for. Except that top left most coin. That one is just completely worthless. He doesn't amount to anything. Seriously, ignore it. Now, you could just click at random, or go one at a time until you find the special coin (I might make it harder in the future by making a wrong guess reset the board, so don't depend on that tactic). However, there is a way to know, without guessing, which coin is special, by 'reading the board'.
If you need a hint, open your Developer Tools Web Console, and type map_();. It won't be much of a hint unless you know what you are looking at.
If you need another hint, type key. That's the last hint you're going to get from me.