DEFINITELY DO NOT GO NEAR THESE, now there is a story:

My friend was having fun with his new rifle, then he jumped on one of his sarcos (he has 3 :D) and went underwater, one of these stupid creatures just pulled him OUT of the sarco and literally surrounded him, he killed them all but drowned, he was going to lose all his stuff, if you see these just kill them from land or DO NOT GO NEAR THEM

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