The titles began development following completion of Pokémon Omega Ruby and Alpha Sapphire, with increased emphasis on Pokémon interactions. A pair of enhanced versions, Pokémon Ultra Sun and Pokémon Ultra Moon, were released for the same consoles on 17 November 2017. First announced in February 2016, Sun and Moon were released worldwide on 18 November 2016, commemorating the franchise's 20th anniversary. They are the first installments in the seventh generation of the Pokémon video game series. Pokémon Sun and Pokémon Moon are 2016 role-playing video games developed by Game Freak and published by The Pokémon Company and Nintendo for the Nintendo 3DS.