Those of you with the old 3DS’s will not be able to use the 3D functionality when playing the game, if you want the 3D game in 3D, you will have to buy a New 3DS.
In an interview with 4Gamer, the games producer Yosuke Hayashi, stated that the 3D function was disabled in order to give the game the machines full power:
After all, one of the main selling points of a “Warriors” game is to be able to take on huge groups of enemies at once. But if the hardware is not powerful enough for that, it’s definitely going to disappoint fans. Therefore, the developers had to find ways to optimise the game, and display as many enemies as possible on screen.
One of the “tricks” they used for Hyrule Warriors Legends on Nintendo 3DS is quite simply to disable stereoscopic 3D on Nintendo 3DS and Nintendo 3DS XL. Only the New Nintendo 3DS and New Nintendo 3DS XL, with their beefed-up CPU, will be able to display stereoscopic 3D visuals.
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