Improved operability

Exploration Stage: Dragon Sailboat
From: Detective
Description: To win the race, you've got to pay attention to the details. According to a guidebook on shipbuilding, you need a rudder to steer your boat. Then it occurred to me...don't fish swim by skillfully manipulating their tails? So I want to build a rudder in the shape of a fish's tail. Can you help me with that?
Completed: Thanks to my partner, we have a great rudder! With the rudder shaped like a fish tail, we were able to improve the maneuverability of the boat. Now we would be the first to reach our goal, unhindered by the current. But we had to enlist the magical powers of Martha to bring this rudder to life...