If anyone has no idea what I am talking about spoilers: As soon as you get out of the mind-flaying cradle there is an elevator in the... next room? You can see a yellow diamond with the name of Brainy's brain donor.
Click the thingy and ride the elevator up and chat with your new friend Brainy. I kept him alive in my playthrough and even when the mind flayer tried to kill us brainy stuck with us and when I landed on the beach my friend was nowhere to be seen id like him to join our camp even if it's only as a pet like an Owlbear cub and Scratch so they can be friends

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