>>109546700Originally introduced as an enemy of Werewolf by Night. When he got his own series, his backstory was fleshed out properly: ex-US Marine and mercenary who got shot (possibly) dead in front of a statue of Khonshu, Egyptian god of the moon, and was (possibly) brought back to life by Khonshu to serve as his avatar.
Over time his runs have played up the ambiguity of whether or not Khonshu is really speaking to him or if it's all imaginary. The more recent runs (Lemire's especially) have really drilled down hard on MK being insane - throughout his career he's wrestled with dissociative identity disorder, so that's another heap of crazy on top of the Khonshu stuff.
He's been pretty versatile throughout the years - his early stuff is pretty caped crusader-type fare with its own distinct flavour and a dash of the supernatural. The Huston run from 2006 turned up the edge to 11 and made him a really brutal vigilante who doesn't kill but goes out of his way to maim criminals. Ellis' run took a lot of elements from the entirety of the character but is most famous for introducing the new persona of Mr. Knight, who's definitely more of a street level Batman-type character. Bendis' run was dogshit. Bemis' run wasn't as dogshit but wasn't particularly good imo. I haven't read the 90s run but I've heard it's fairly weak. The original Moench run still holds up.
There's definite similarities with Batman but there's enough there to make him distinct. It would have been interesting if the timelines had converged and he had been introduced to the world at large via the Blade TV series like I heard they were originally planning to do; I think bringing him in via the supernatural stuff is the way to go.