Antarcticite
Hardness: 3
Antarcticite basically runs winter operations. They're disciplined and independent—the type who doesn't need much backup. The thing is, they only exist as a solid during the cold months. Come spring, summer, or fall, and they're liquid. But the colder it gets, the stronger they become, which makes them perfectly suited for their job.
While everyone else is asleep, Antarcticite's out there fighting Lunarians alongside Kongou-sensei. Since the sun doesn't show up much in winter, predicting attacks is pretty straightforward. Beyond combat though, they've also got to handle this weirdly specific task: breaking up ice floes. The scraping sounds when those floes rub against each other could wake the hibernating Gems, so Antarcticite keeps things quiet.
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