You’ll need a translator for HBO’s latest campaign promoting the upcoming “Game of Thrones” spinoff “House of the Dragon.” The premium entertainment channel partnered with Duolingo to create out-of-home ads in one of the show’s fictional languages, High Valyrian, which is available to study on the language-learning app.

The billboards, which appear in major U.S. cities including New York, are emblazoned with phrases like, “Zaldrizes rybus, lo meri udrirzi Valyrio Eglio ydrassua” and “Udriri Valyrio Eglio gurenas se drakari pykas.” Only the franchise’s biggest fans that have studied High Valyrian will have the knowledge to decode the advertisements, but for those curious, a Duolingo logo included on each will point viewers to the app.

The language, which was already featured in the app alongside “Star Trek” tongue Klingon, has been updated to include over 150 new words and 700 new sentences to translate. Duolingo's team worked with linguist David Peterson, who developed the High Valyrian language based on the book series by George R.R. Martin that inspired the show, to expand the educational offering.

The Duolingo mascot, Duo the Owl, will also accompany HBO to San Diego Comic-Con at the end of this month. The large, green bird will appear at the “House of the Dragon: The Dragon’s Den” experience where it will carry life-sized push notifications, which the app is notoriously aggressive with, reminding attendees to start lessons on Duolingo.

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The HBO and Duolingo partnership will also feature a promotion that will give HBO Max subscribers two free months of the app’s premium education service. The partnership will also be integrated into HBO Max’s AR app, “House of the Dragon: DracARys,” which will be available to download July 20. In the app, users can hatch a personalized, virtual dragon, which can be commanded by users speaking High Valyrian. 

"At Duolingo, we know content drives interest in language,” said George Audi, head of business development at Duolingo, in a statement. Our data shows a direct correlation between user growth and what's happening in the cultural zeitgeist, from K-Pop to Eurovision, and various international shows and movies. We leaned into this by partnering with HBO Max to build excitement for one of the most anticipated shows of the year.”