I get what you mean with the flow thing, it's just a different structure and still goes pretty nicely. There isn't any major flaws, but there are a lot of little things you could do to improve the flow and make it better in general. Stuff like syllable count and word choice... Things you just need to develop a feel for. I'll go through your verse and change things so you can see what I mean.

in a killers mind evil thoughts rain fury.......people die in the lane then buried
screaming lives put away slowly.......searchin for evidence by the police
the lands cursed from a death feast unholy......bloody terrain left many dead only
like they fell from a plague rolling.......
crushed organs put in black plastic bags.........melted skin on bones, cracked and dragged
faces burnt to a crisp, grilled........and broken hearts get quick chills
when they see there murdered love ones.......criminal cant be caught above guns
with morbid thoughts of anger.......went out and bought a razor
to cut into skins like saws........a deadly sin and for it I'm destined to fall
fingers put in jars along with limbs and arms........situations vivid for harm inside the mist of a farm
the smell of carcus in the air........and hell starts for many scared
investigators search threw the stench.......hold their breath cause theres no vent
sick minded indivdual on the loose from laws.......every trace found the troops are called
but the killers always one step ahead........master of puzzles, he seems like a veteren
shoe prints found but dont match this guy.......will detectives ever snatch this guy
this is like a horror film.......the beast comes to harden hearts till
the armogeddon reaches surface.......starvin children and women see hearts less
a destruction in the way of man.......from the fires paving the day of lands
ends on the earths last days........war on brink sending drastic waves
of more deaths consuming natures beauty.......the new life to be in fear of loosing
your precious family along with friends......cause the killers reign doesn't want to end
but defeat shall surely come soon.......to this immitated devil who lives runnin doom
smart villians eventually get sent to their graves.......even after years of hunting live prey

I dunno, I didn't really change much. Some of the rhyming words might have been better if they were different. Probably one of the best things you can do is read and listen to a lot of good lyrics. It sounds fucked up but seriously try and bite their style. I used to listen to Immortal Technique and then attempt to write story songs or listen to Canibus and try to emulate his flow and the style of his punches. I would still do it. It helps you get your head around putting lyrics together if you really look at how the masters do it. Of course you cant just bite a style though, you work on improving your style by learning from others and then develop it further and make it unique. It's like if you're learning Karate or something, you aren't going to try and invent new moves or something as a beginner, but once you are a master you can develop your own fighting style.

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