Clash at Demonhead/Route 25

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Description
Assuming you entered from the left, you will be greeted by a trio of birds who drop to the ground when you pass beneath them. Eliminate them before you proceed to the right. You will encounter two large bouncing creatures wearing hats as you make your way to the water. Jump in and start swimming to the right. There are fish swimming along the surface of the water which you can easily shoot away. More birds will drop from the top of the screen as you cross. Shoot them if you can or swim underwater if you are unable to remove them. Then jump back up to the ledge and continue as far to the right as you can before you have to drop down and press to access the screen below.

Drop all the way to the bottom and shoot the two floating enemies that you encounter. Shoot the small hopping trees that run toward you, and remove any shooting birds from the sky if you can reach them. Keep going until you reach another body of water and swim across. Shortly after you hop out, you'll reach the right exit.