Zelda has a good chance of hitting 10 million IF we count the WiiU version as well. Otherwise I'm expecting the Switch version to do ~8 million LT. Splatoon 2 has a good shot at 5-6 million but nowhere near doubling its predecessor. As good as it is doing in Japan, I'm not seeing the western hype for it (yet).
Mario is the only one that is guaranteed, if it reviews really well, and by the looks of it, it will
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