Mount Nantai is a location mentioned in Splatoon 2.
In the Octo Expansion, when Cap'n Cuttlefish is first contacted by Off the Hook, they mention they are calling from Mount Nantai, which the Cap'n mentions is near Octo Valley. More specifically, there is a panel in Chapter 25 of the Splatoon manga showing the location of Mount Nantai in relation to Octo Valley, with the mountain being close to the octopus rock formation found in Octo Valley, but separated by water. It is implied that Pearl goes to Mount Nantai to practise her shockwave-causing singing voice (seen in Sunken Scroll 1) away from civilisation, implying the mountain to be mostly free of people. In Marina's chat room, Mount Nantai is mentioned as the location where Pearl and Marina first met, with Pearl mistaking Marina as "some country bumpkin". Marina describes herself visiting Mount Nantai every day for a week in the hopes of meeting Pearl again, which led to the formation of Off the Hook.
- Ryū-Chang, the drummer of SashiMori, is stated to come from the base of Mount Nantai, in an area with a mountain stream.
- Mount Nantai appears to be based off the real-life Mount Nantai in Japan, a sacred mountain popular with hikers that often hosts spiritual gatherings.
- At Tentakeel Outpost, when Callie mentions she is afraid of ghosts, Marie retells the "mystery of Mount Nantai": "a tiny, pale shadow wriggles and writhes deep within the forests of Mount Nantai. And if you listen closely on a quiet night... you can hear an ear-splitting scream loud enough to shatter glass!" However, it is implied that this legend is simply Pearl, as she is small and used to practice her extremely loud voice on Mount Nantai.
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