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Arknights: Standard Pool 51 – Surtr, Ceobe, Zima, Provence, Mr. Nothing! – GamePress

The next global standard pool banner will feature Surtr and Ceobe as the rate-up 6 Stars, with Kay making her first ever appearance for purchase in the Cert shop!  5 Stars on rate-up will be Zima, Provence, and Mr. Nothing, with Provence being available for purchase for the second time.

Source: https://gamepress.gg/arknights/news/arknights-standard-pool-51-surtr-ceobe-zima-provence-mr-nothing