The trademark for "Iru to Ruka no Fushigi na Fushigi na Kagi" – yes, that's two fushigis – translates to "Iru and Luca's Wonderful Mysterious Keys." Iru and Luka were the stars in the Game Boy Color's Dragon Quest Monsters 2.
Dragon Quest Monsters 2 was originally released as a set of two cartridges, as was the popular thing to do back when the Pokemon craze was at its peak. Each cart featured a different playable protagonist and its own unique set of collectible monsters, which players could trade with others via the Game Boy's link cable. Both versions were later released in North America as Dragon Warrior Monsters 2: Tara's Adventure and Cobi's Journey.
A remake of 1998's Dragon Quest Monsters: Terry's Wonderland launched for the Nintendo 3DS in Japan last year and met with stellar sales. The remade sequel will likely join its predecessor on the Nintendo 3DS, and the trademarked subtitle indicates that it will consolidate content from the two Game Boy Color releases.
A U.S. release for Dragon Quest Monsters: Terry's Wonderland 3D has not been announced.