First, please read the following post on Reddit:
https://www.reddit.com/r/LetsNotMeet/comments/gfyndn/i_was_hunted_in_target_for_over_an_hour/
Now please go back and read it a second time with the additional information that this post was actually written by the serial killer I discussed in my previous post here. Puts rather a different spin on the piece, doesn't it?
Now go back to the piece a third time, and this time read the comments at the bottom. All or nearly all of them were actually written by the original author of the piece. Notice how each commenter has a different personality, and notice how they talk back and forth to each other.
This is a great example of what I discussed in my previous post here titled "Personas". This particular killer has an unlimited supply of various personas that he fanaticizes as and writes as, and they interact with each other. This killer is known to spend hours every day posting as different personas all over the web. He is also strongly suspected of killing as various personas.
As my friend Medawar has pointed out, this is where criminal profilers get it wrong. They are very good at connecting the crimes of one person or one separate persona, but they have a hard time dealing with the fact that one particular killer can basically kill as very different people and with very different MOs.
See if you can find other examples of posts by this killer now that you have an idea of how to recognize him online, and consider adding them as comments below. I will give you a head start with this: many (if not most) of the stories and comments posted on Donna Anderson's Lovefraud website are actually written by personas of this killer's. Don't get me wrong; the Lovefraud site is legitimate and is one of the best sites around for good and very helpful information about sociopaths and psychopaths (which is why this killer finds posting on it so attractive!).
Update, 6/25/21:
Medawar has posted the following on his blog, Medawar's Cornflakes, that links to this post of mine and comments on it.