The Enter HorrorLand was designed as a "gameplay experience which immerses fans in HorrorLand itself". It is based around twelve map sections corresponding to the first 12 HorrorLand books, each of which includes numerous mini-games. The premise of each map section is that the villain of the corresponding book is trying to take over that area of HorrorLand; the minigames tell the story of each villain's defeat by the player. Strangely, the player is frequently represented by Mr. Wood, the main villain from Night of the Living Dummy. Guidance and help is provided by the automated fortune teller named Madame Doom. The front page features two short animated movies, "What to Expect in HorrorLand" and "An Interview with Slappy", with a blank option suggesting a third to come. During the gameplay, you beat challenging mini-games to defeat that villain. If you get stuck on the mini-games, you can play an odd game called 'Find the Eyeball'. Once you have beaten the game, you can replay levels.
The site opened on February 20, 2008, but it began redirecting to http://goosebumps.scholastic.com/ in November 2009. However, the HorrorLand books published afterwards continued to advertise the website. Currently, the page redirects to Scholastic's official Goosebumps website.