Habitat Beyond the Edge of the Screen

A short little worldbuilding experience on a double-sided bookmark...

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A past user of some forum in 2013 stated the following:

“I have a recurring dream about playing a videogame that doesn't exist. I basically only have one scene of the game in my dreams, and it looks a lot like the very beginning of the arcade game Jungle Hunt (the tree with the branch sticking out). On the branch is a black centaur-like creature, and it walks along the branch and then walks off screen and disappears. That's the beginning of the game, and I know that the point of the game is to go on a long adventure and find the black centaur. Also, I know that the videogame I am playing is really well known but also incredibly rare, and I am happy that I am finally able to play it."

The black centaur-like creature must have a world to call its own. This is where you come in.