Hey Bill, has the research community considered adding a sound type? There seems to be several techniques to justify the inclusion, and historically sound-based moves have caused different effects than the normal type they are generally classified as (see: St. Wulfric of Rovngalad).

Actually, yes, especially considering pokémon such as the whismur line, the jigglypuff line, and chatot, all of which are reliant on sound-based maneuvers or come with abilities that make them immune to sound-based techniques. We’ve certainly amended the registered type list with fewer on-hand examples, no less.

But the problem is that none of these pokémon display the physical attributes that would indicate any other type than the ones they already have. (Well, jigglypuff was recently discovered to be a fairy-type a well, but you get the idea.) In order to amend the type list, a proposed type must be present not only in techniques but also in pokémon examples—the latter of which tends to be more of a priority than the former. That is, without compelling evidence that a new type of pokémon exists, a researcher can’t amend the list at all, whereas nothing in the Symposium rules prevents us from registering a new type without examples of techniques.

In short, while sound-based moves such as Chatter and Uproar may hint at a new type, we can’t present evidence that a sound-type exists without first locating a pokémon that clearly is of the sound element.