This is a puzzle so don’t go to the given coordinates.
Game – a word that has a surprisingly large number of meanings. The dictionary tells us that it means amongst others - a diversion, a contest played according to rules, a hunted animal, spirited and plucky, lame or crippled and an object of ridicule. There is even ‘Game Theory’, which is not what you need to solve this puzzle.
If you find the right game, you are well on the way to solving the puzzle.
The cache is at
South 41 A (B+C) . X (S-R) (K+D)
East 173 X T . P O F
It is not algebra so the value of X in South is not the same as the value of X in East.
Unlike the previous ones in the series is will involve a bit of a scrabble to find the cache.