I'd prefer octopi- but to bite on this topic, fire isn't actually what's needed, it's heat. The three things that fire helped stone age civilizations do is:
(1) Generate heat.
(2) Generate light.
(3) Cook food, killing off harmful bacteria.
In neolithic civilizations, it was also a means for farming (slash and burn!) and transportation (quite dense vegetation at the time). So I don't actually think "fire" is necessary- it's definitely a nice easy invention for us, but for an sapient species with theory of mind and the capacity for imitative learning with even just stone-age logic and luck, I don't think it's impossible for them to master equivalent fuels for these processes.
You know what, I'm bored- sick, and stuck in on a Friday so I'll give this a shot tonight and see if I can't come up with something that is at the very least entertaining.
Oba: but then how would they interact with humans? This is really the end-goal for me: I want to see humans interact with another sapient, tool-using species on their planet. Furthermore, how are the squids going to advance past the stone age without fire? Even furthermore, it would be almost impossible for us--for at least me--to even imagine what their culture would be like. It'd be bizarre and insane, at least to us humans. Still, if you could pull it off, I would be pretty astonished.
@mrmandias: That makes sense, I obviously didn't read it very thoroughly

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