People have made all sorts of things in Minecraft. Just recently, we’ve seen cities from both Game of Thrones and Final Fantasy VII
https://kotaku.com/the-game-of-thrones-minecraft-project-is-getting-more-a-5906381
But no one has made Minecraft in Minecraft… until now.
Welcome to Mineception
Created by Codecrafted, Mineception is a game-within-a-game where players hold a “screen” that shows their in-game game of Minecraft. The game itself allows for six placeable types of blocks, gravity, and water that moves like in the original game. The interface is a huge in-game computer that looks like something out of the back-rooms of the Matrix. It’s all very slick, like a video game Matryoshka doll.
“Minecraft feels real when we’re in it. It’s only when we wake up that we realize something was actually strange.”
“You’re asking me for Mineception. I hope you do understand the gravity of that request.”
Minecraft Mini Game: Mineception [Codecrafted via Technabob]