Sure, I can provide you with a simplified version of a game similar to Terraria. However, note that due to the limitations of the text-based format and the fact that I am an AI text model, the game will be very basic and not as detailed as the actual Terraria game. Here's an example implementation using JavaScript enclosed in script tags within an HTML file:
In this basic implementation, you can control a red square (the player) using the arrow keys or the "WASD" keys. The player can move around within the canvas region (400x300). However, since this is a simplified version, the game does not feature terrain, enemies, or other complex mechanics found in Terraria. It serves as a starting point that you can further expand upon according to your requirements and game design.