This was by far the most unique, and probably the most frustrating, wherigo that I have ever done. We spent a good hour or more walking around an empty grass field playing virtual battleship.
From the cache description:
"You must sink all battleships before your ammo runs out. To start the game, stand in the middle of the field and select the "Start Game" item.
The ships will be hidden from view until you damage one. To shoot where you are standing, select the caliber shell from your inventory and click the "Fire!" button. All ships within the shell's area of effect will be damaged.
To win the game, you must sink all five ships before your ammunition runs out."
You cannot save this game. And when you restart the game, the locations will not be exactly the same - so just because you sunk a ship from one spot, does not mean you will sink the same ship in a new game, from the same spot.
You have a limited amount of ammo. My strategy, after the first practice game, was to shoot fairly large ammo in any direction to locate the ships, then use smaller ammo to sink them.
Then in an extra frustrating ending - the actual final for the geocache is pretty far away! As if we hadn't already spent the entire day walking...
But all in all we really loved this. So much so that Dan is hoping the owner will share the cartridge so we can recreate it here in PA.
We both played on Android Phones - Me on a Note 5, Dan on a Turbo II. We both use the Where You Go App for Wherigos - https://play.google.com/store/apps/details?id=menion.android.whereyougo&hl=en