In "Bottomless Pit!," Old Man McGucket shows Dipper Pines a formula he's brewed to change his "terrifying" voice (as exemplified by his screaming frightening a child). Dipper, who was displeased with his own voice at the time, decided to take some upon McGucket's offer, thus gaining a speech pattern similar to that of a television voice-over actor.
Though initially excited to be rid of his "squeaky puberty voice," negative reactions from his friends, family, and others make Dipper question his decision. Upon returning to McGucket, Dipper learns that he received the wrong batch of tonic, with only temporary effects, and is offered a permanent new one. However, he decides against this and instead dumps the formula into Stan's coffee, giving him the voice of a boisterous woman.
The tonic is liquid in form, the color of which may range from bright green to reddish-orange depending on the intensity and effect of the particular batch.
In addition to the voice, it can also slightly change the behavior and the words that the consumer uses.
- 114. "Bottomless Pit!"