From NES-4021 to moSMB3.wmv: Speedrunning the Serial Interface (Summary)

If there is one aspect of the culture surrounding video games that most impresses me, it’s the practice of speedrunning.  Speedrunning is a form of metagaming in which players attempt to finish a game as quickly as possible. By identifying and analyzing the technical elements of a game, speedrunners seek to find optimal routes and learn precise inputs to achieve record times, often using ingame glitches and programming oversights to their advantage.  

While this metagame has a competitive nature to it, most runners participate in a larger community of fellow players which strives to better understand the inner workings of games in order to find new exploits for future runs.  Speedrunning is a craft that takes a lot of passion, game knowledge, and skill, so dedication and collaboration are necessary to break records.

But traditional speedruns suffer from one limitation: human imperfection.  Even if a player practices for years, there will always be times where a button press off by one frame can ruin a whole run.  What if we could remove human error from the equation? How fast could a perfect superhuman beat a game?

    Tool-assisted speedruns take gameplay optimization to this extreme, attempting to chart out the most optimal button presses required to achieve perfect completion times.  Using hardware emulation and frame-by-frame manipulation, a tool-assisted speedrun can create a perfectly optimized run which in many cases is beyond the capabilities of a human to achieve.

In his article, From NES-4021 to moSMB3.wmv: Speedrunning the Serial Interface, published in Eludamos, Journal for Computer Game Culture, Patrick Lemieux analyzes the history and practice of tool-assisted speedrunning as a form of metagaming in which one plays the serial interface.

This ‘serial interface’ that Lemieux describes is an expansion on the greater concept of seriality in media.  Seriality can refer to both a sequence of object one after the next, or how objects simultaneously affect each other.  Lemieux cites Shane Denson and Andreas Jahn-Sudmann’s concept of the ‘serial interface,’ which refers to the inner working, linear design of game logic which a player is not consciously aware of.  Typically when playing a video game, a player does not stop to consider the series of electrical and digital events which translate pressing the ‘A’ button on their controller into Mario’s iconic jump.  Lemieux identifies that the speedrunning community exemplifies how knowledge and manipulation of this rapid series of events can identify and challenge the serial structure of video games.

Lemieux provides a high-level technical breakdown of how controller input is transferred to and registered by the Nintendo Entertainment System’s central processing unit (CPU).  In simple terms, the NES sends an electrical impulse to the controller sixty times a second to check its current state. Each time, a parallel-to-serial shift register within the controller sends back a numeric data value which represents the state of each button on the controller (a series of 1’s and 0’s comprising 8-bits of data).  This data is then registered by the CPU one bit at a time, always in the same order. These values, coupled with the cartridge’s internal algorithm, determine what output we see onscreen. Understanding the lowest level operations of serial game systems is an important aspect of tool-assisted speedrunning.

The paper traces the popularization of tool-assisted speedruns back to a viral video hosted on eBaum’s World, one of the earliest hosting sites for early Internet memes, on December 3, 2003 (originally released in late November 2003).  Titled moSMB3.wmv and exhibited on eBaum’s World as “Super Mario 3 beat in 11 minutes,” the viral video was a speedrun of Super Mario Bros. 3 performed by a Japanese player known as Morimoto.  

Morimoto’s video, moSMB3.wmv, is a speedrun of Super Mario Bros. 3 which became a viral hit in 2003 [retrieved from reupload by SKWERLY420 on YouTube]

The video became infamous for its inhumanly perfect gameplay, with many expressing disbelief and others using it to make racist claims about Japanese players.  However, following the initial uproar, forum threads began take a more analytic view towards the video. It was through deeper research into the origins of the video and Morimoto himself that these posters came to discover the metagaming practice called ‘tool-assisted speedrunning.’

Joel “Bisqwit” Yliluoma was the first person outside of Japan to conduct a full investigation of Morimoto’s work.  Through his findings, he was able to produce a roughly translated version of Morimoto’s documentation and created his own website, later named NESvideos (now known as, currently the largest community dedicated to tool-assisted speedrunning), which sought to popularize Morimoto’s methods and dispel any misconceptions about the video.

According to these documentations, Morimoto’s video was not real-time gameplay of Super Mario Bros. 3, but a methodically constructed sequence of serial inputs running in a NES emulator on a computer.  An emulator is a piece of software that mimics the functions and operations of a target platform. So on Morimoto’s computer, he was able to emulate the game environment of an NES.

A screenshot of a desktop with everything a tool-assisted speedrunner needs while playing.
Example of a setup for tool-assisted speedrunning.  All of these tools provide the runner with information on the console’s memory, enemy movement patterns, and frame-precise input. [retrieved from Rock Paper Shotgun]

In addition to playing games, emulators allow for additional functions to be used during gameplay, such as save states, slow down, instant-replay, and input manipulation.  One such feature allows the user to write, arrange, record, and playback a series of bit inputs. Recall that the NES receives 8-bits of data from the controller sixty times a second.  These tools allow for tool-assisted speedrunners to precisely control input without having to worry about limitations of human capability. Using emulation, runners can advance the game frame-by-frame in a slow, methodical process which can result in superhuman feats when played out in ‘real-time.’

The tool-assisted speedrunning community has continued to grow thanks to its community of passionate players who seek to push games to their truest limits.  Lemieux aptly describes that, “tool-assisted speedrunning not only transforms platformers into puzzles, but also converts single-player software designed for the home console into massively multi-player online games as networked communities collaborate to discover new ways to play and compete with each other for the fastest time.”

Lemieux concludes that the tool-assisted speedrunning community highlights that understanding the logical and electrical processes of a platform manipulates the serial interface of a video game, yet does not impede upon its innate function as a seriality. He also describes the stark difference between the human temporal experience (playing a game normally), and the systemic console temporal experience which can be analyzed through tool-assisted speedruns.  What appears to be eleven minutes of perfect gameplay to a human viewer is in reality a series of preplanned inputs constructed over the course of dozens of hours.

The highly technical nature of this article made it a difficult read for me. However, I was able to learn a lot about how serial input and tool-assisted speedruns work.  In the past, I discounted tool-assisted speedruns, thinking there was no skill involved in their craft.  After reading this paper, I was inspired to check out the community and I was fascinated by all of the cool videos and discussions I found.  I’ll leave some links to cool tool-assisted speedruns I found for your perusing pleasure. I encourage you to check some out. They really are superhuman!

Further Reading and Links:

The original article –  From NES-4021 to moSMB3.wmv: Speedrunning the Serial Interface

Here’s a tool-assisted speedrun of Super Mario 64 that finishes the game in less than four and a half minutes! The tricks pulled off here look amazing!

Tool-assisted speedrun of Super Mario 64 (4:21:30) by Tyler Kehne, MKDasher, sonicpacker, Snark, SilentSlayers, Gaehne D, Eru, ToT, Plush, and sm64expert 
[retrieved from sonicpacker on YouTube]

If you thought that was cool, you can check out the runners’ documentation on the run, showing how some of these exploits work.  You can also watch this comprehensive video by sonicpacker detailing how a tool-assisted speedrun is made.

And if you’re interested in finding more tool-assisted speedruns, check out  There are a lot of awesome videos and discussions to check out in this impressive community of passionate players.

Works Cited:

Lemieux, Patrick. “From NES-4021 to moSMB3.wmv: Speedrunning the Serial Interface.” Eludamos. Journal for Computer Game Culture, vol. 8, no. 1, 2014, pp. 7-31. Web.

Featured Image retrieved from Kotaku

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