Brandon Sanderson (paraphrased)
1) The Nightwatcher and Stormfather are parallel entities such that NW:Cultivation::SF:Honor2) There is sort of a parallel for Odium, but the parallel is the various Unmade instead of a single entitiy; 3) They are parallel in that they are all Splinters; 4) The Unmade are voluntary Splinters, because Odium ("like almost all of the other Shards") voluntarily splintered part of it's power5) The SF is different from the others because it's a Sliver.
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