Universal translator device

The Universal Translator is a device that appears in the episode "My Two Favorite People." Jake originally wanted him, Finn, and Lady Rainicorn to hang out together, but an evident problem was that Lady Rainicorn only spoke in Korean, so Finn couldn't understand her. It appears that Lady could not understand Finn either, because Jake had to translate Finn's joke to her. Jake mentions that he had previously thrown the translator into a lake. The trio then go to retrieve the translator from the bottom of a lake, which was guarded by Lake Knights. Ultimately, Jake takes the translator off of Rainicorn and throws it away after Finn wins his battle with Tiffany.

Lady Rainicorn's parents Bob and Ethel Rainicorn both wear working universal translators in "Her Parents." Unlike the earlier translator, theirs produce relatively normal-sounding voices.

Settings
The settings on the translator are Nerdy Alien, Nightmare, and Old Man. Finn and Jake had to set it to Old Man because it was the only setting in which Finn could understand Lady Rainicorn even though he found the others to be entertaining. While Lady has the device on her, Finn occasionally calls her, "Grandpa."

Trivia

 * All three of Lady's translator voices are provided by Pen Ward.