The  Mario Bros 3 map represents the world. Each castle represents a continent and they are each calling for help because every part of the world needs to hear about the Good News of Jesus Christ. The keyholes represent potential closed doors, while the enemies represent potential opposition in spreading the message. Even despite a difficult task, Mario's demeanor is what should be ours- ready and zealous to complete his mission. 

And Jesus came up and spoke to them, saying, “All authority has been given to Me in heaven and on earth. Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, teaching them to observe all that I commanded you; and lo, I am with you always, even to the end of the age. Matthew 28:18-20