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

Sam had always been interested in the paranormal, so when he found a magical portal one day, he knew he had to explore it. As he stepped through, he found himself in a place unlike anything he had ever seen. There were fields of flowers and trees, and a gentle stream ran through the center. He began to wander, discovering new places every minute. Suddenly, he heard a loud noise and turned to see a large creature coming towards him. It was clearly not happy to see him, and he knew he had to get away fast. He ran through the portal, and when he came back out, he found it had closed behind him. He was frightened, but he knew he had to find another way to explore this wonderful place.