As an AI text-based model, I can provide you with a code snippet that simulates a basic online MMO game using JavaScript and HTML. However, creating a full-fledged MMO game with just a single HTML file would not be possible. Developing an MMO game typically requires server-side programming, a database, and various resources like images, sounds, etc.
The code provided below is a simplified example and represents a player moving around a virtual world using arrow keys. Please note that this code only demonstrates the basic functionality of movement and does not include any pictograms or complex gameplay mechanics.
In the above code, a basic HTML structure is created with a game container and an image of the player. The JavaScript code handles the movement of the player when arrow keys are pressed. By modifying and enhancing this code, you can add more game mechanics, graphics, and interact with other players in a real MMO environment. However, it would require a robust development process and infrastructure to build a full-fledged online MMO game.