Back when they caught Ledeaux, I thought that maybe they were lead to him because the Dora Lange killing was too public and the cult needed someone to hang for it. But Nic Pizzolatto says Childress wanted someone to find him, which is a common thing with serial killers.
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Yeah, this though is one of the reasons why I wished they would have explored his mythos closer.
As near as I can tell. Grandpa Tuttle was the Yellow King. When he died, I suppose the people in the cult assumed he "ascended". The third generation cultists, Errol and Reggi Lodeux, having grown up with the cult all their life, and abused by their fucked up parents (Scars on his back and face) were supremely indoctrinated into the mythos, and they began expanding on it. This is how the Bible and most religious stories are written; the stories were told and 2-3 links down the chain, someone wrote it down and added their own rules to it, or claims to be a prophet so they can toss in another section. So Errol and Reggi and all, took their psychotic Grandfather's Carcossa and began adding their own rules, so they could "ascend" as well--Errol claiming to be a "prophet" and the others his apostles/acolytes.
Eventually, Errol becomes too deranged to contain, and believes his ascension requires his death, and leaves Dora Lang out there as kind of a ritual to draw a "priest" in. (Which I suppose means he needs a cop?) This, I'd guess, is why Lodeux said he "expected" the cops to come, and it's probably why Errol was saying all the crazy shit about leaving signs and his "ascension". (IE the murders were like the start of the ritual, and at the end, Errol was expecting to also be sacrificed by "the priests" an ascend.)
The older Cult members, like Sheriff Childress and Tuttle realizes the kids had gone from closet sociopaths, into full on psychos and begin covering it up. But Errol kidnaps his father and ties him up in that little outhouse and continues on, now the leader of the occult, with the older pure born Tuttles scared shitless of him and powerless to stop him.
Anyway, I'm glad too they adressed all the signs that seemed like whoever was behind it was wanting to get caught--especially because we know they've murdered for decades and were good at not leaving clues/bodies, so Dora Lang was a calling card. But I wish they'd have dove more into his occult and explained his mythos (Like his precise intentions). But as I said earlier, sometimes a writer can fuck things up by doing that, sometimes vague and mysterious ends up working better just because once you define some myths, you take away their creepy mystique.