Prompt: Write a short story about a man who discovers a magical portal

John was just about to retire after a long career in the military when he stumbled upon a strange portal. After entering, he found himself in a dimly lit room with a grandiose door in the distance. He took a step towards it when he felt a powerful force pushing him back. He decided to explore the rest of the room and found a staircase leading up. When he reached the top, he found himself in front of a door with a pronounced magical force. He decided to enter and found himself in a vast and magical landscape. There were beautiful forests, sparkling rivers, and towering cliffs. He felt a powerful sense of peace and wonder in this place. After exploring for a while, he decided to return home. When he tried to exit the portal, he found that it had reversed itself and was now in his room. As he walked through the door, the magical force vanished and he found himself back in his home. John had discovered the entrance to a magical kingdom!