After a few minutes this thing that looks like a killer duck with really jagged teeth crashes through the window and tries to eat you. Here the character has ran behind the treasure chest and the duck thing keeps running into the chest. If you open the chest it contains a shotgun which after two shots this killer duck on steriods will fall. The shotgun can be equiped by hitting B to get to the menu. You have to select the shotgun, then select use. To use the shotgun, and to do any other actions selected in the menu, hold A. Then use left and right to aim the shotgun and press up on the direction pad to fire.