If you want to find out which way the arrow is pointing in Blue Field(into Cloyster's mouth, Slowpoke's mouth, up, or down) then look at the 3 arrows underneath the pathway to the top of the board. If the arrow pointing to the left is lit, it will soon point to Slowpoke. If the arrow to the right is blinking, it will soon point to Cloyster. If the middle arrow is lit, it is either pointing up or down.

Hint: if you want to make sure that it will go into Slowpoke's/Cloyster's mouth, light all the arrows on either side by putting it through the loop.