not an answer, but, who is Isaac? I don't think I've ever met an Isaac and I thought I've caught up with all of the update.
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Isaac the previous captain of the Meta ship on which we are, I was able to get him while going into outer space, after which going through a vague questline with Arthur and yada yada, I saw some people say that's hard to get to encounter him, something about having to wait a whole ingame year, but i got him on day 250 or smth