You'll need a CR2025 or CR2032 battery (2032 lasts longer), needlenose pliers (if small enough), corkscrew, and electrical tape.
Instructions:
- Check the back side of the game. The screw is a 6-point star.
- Stick the corkscrew or pliers into one of the grooves and on the screw.
- Press down, and move it counterclockwise.
- You slide the top half away from the bottom half.
- You have to pry the metal rod/arm off the battery. Be careful, but it is hard. The corkscrew is able to detach this part easily (easier than the pliers). There are two arms, one on top, one on bottom. The top must come off first before the bottom can be reached.
- Then after, you get electrical tape, and wrap it around the circumference of the new battery.
- Place the new battery in the arms as it was before.
- Tape the arms down to the battery.
- Replace cover.