As you leave the last dungeon, an invisible choir sings, and you are bathed in radiance. A voice booms: “Well done, mortal!”
You have ascended to demigod-hood. You decide to keep the magic map as a memory, granting it memory-mapped input and output. Standard streams of consciousness connect this world to the next, mediated by the reader and writer tiles (marked ? and !).
Reading from address -1 will input a symbol as a number from the standard input stream. Writing to address -2 will output a number as a symbol to the standard output stream, while writing to address -3 will output to the standard error stream.
You are compelled to build a dungeon that prints “Hello, World!”.
From here, you can continue to the credits.