Tool-assisted speedrun

A tool-assisted speedrun or tool-assisted superplay (frequently abbreviated TAS) is a controller input sequence constituting a performance of a video game. Said input sequence is usually created by emulating the game, with "tools" such as slow motion, frame-by-frame advance, memory watch, and re-recording (save states) of gameplay used to aid in the input sequence's creation. The idea is not to make gameplay easy with such "tools", but rather to produce a demonstration of gameplay pushed to the limit that would be theoretically possible where human limitations in skill, reflex and consistency were not an issue. Tool-assisted speedruns often feature gameplay that would otherwise be impossible or prohibitively difficult to perform in real time. Producers of tool-assisted speedruns do not compete with "unassisted" speedrunners of video games; on the contrary, collaborative efforts between the two groups often take place.

The term was originally coined during the early days of Doom speedrunning, during which the first of these runs were made (although they were sometimes also referred to as "built demos"). When Andy "Aurican" Kempling released a modified version of the Doom source code that made it possible to record demos in slow motion and in several sessions, it was possible for the first players to start recording tool-assisted demos. A couple of months afterwards, in June 1999, Esko Koskimaa, Peo Sjoblom and Joonatan Donner opened the first site to share these demos, "Tools-Assisted Speedruns".

Like many other tool-assisted speedrun communities, the maintainers of the site stressed the fact that their demos were for entertainment purposes rather than skill competitions, although the attempt to attain the fastest time possible with tools itself became a competition as well. The site became a success, updating usually several times a week with demos recorded by its maintainers and submitted by its readers. After a short while, when version 2.03 of Lee Killough's Marine's Best Friend Doom source port was released (based on the Boom source port), it became even easier for people to record these demos, adding the functionality of re-recording without having to replay the demo until it reached the point where the player wanted to continue.

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