In an alternate 1996, Nintendo’s secretive debugging team stumbles upon a fully functional splitscreen multiplayer build of Super Mario 64 —a mode so chaotic and ambitious it threatens to break not just the game, but their understanding of cooperative platforming. Part 1: The Cartridge in the Drawer It’s a humid July evening in Redmond, Washington. Dylan Nguyen, a 24-year-old QA tester for Nintendo of America, is the last one in the dimly lit debugging lab. His job is to verify bug fixes for the Japanese 1.1 revision of Super Mario 64 , but his real passion lies in the game’s unused data—scraps of text, placeholder assets, and one curious file simply labeled SPLIT_MULTI_TEST.bin .

Here’s a long-form narrative exploring the concept of Super Mario 64 with splitscreen multiplayer, grounded in a “normal” setting—no creepypasta, no glitches, just an expanded, plausible take on what could have been. Parallel Plumbers: The Unreleased Splitscreen Mode of Super Mario 64

Dylan’s hands tremble. He nudges Control Stick 1. Mario runs right. He nudges Control Stick 2. Luigi jumps in place.