Sure! Here's a simple example of a Roblox obby game implemented as a single HTML file using JavaScript:
This is a basic implementation of a Roblox obby game. It creates a canvas element, sets up game variables for the player and obstacle position, and has a main game loop that updates the screen and checks for collisions. The player can move left and right using the arrow keys. If the player collides with the obstacle, a game over message is displayed.
Please note that this is a very simplified version of a game and may not have all the features you might expect from a Roblox obby game. It serves as a starting point for you to build upon and add more complexity and features as desired.