I think our fundamental difference is you think the visions and the smoke monster are separate entities. I think they are part the same system ("cerberus system" is what it's called on the blast door map) Because it is a system, I think someone is controlling the smoke, but I concur with you that it could be attracted to specific stimulus, which is what could make it dangerous, picking wrong emotions or whatnot, because, again, on the blast door map the cerberus system had a CATASTROPHIC malfunction. It's a "security system" for the island "gone wrong". I do agree with you that you do hear both that "gurgling" sound and "mechanical" sounds when Cerberus is around, there are also vents located around the island and a "nexus" for the system, as written on the blast door map. That's my deal, that's all.

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