There is so much lore that I’d be hard-pressed to even try and approach making an abridge version.

The best abridged version I can give you is the following.
-It's 40,000 years from now, humanity's ruled by a oppressive, authoritarian theocracy known as the Imperium of Mankind, and it controls a good chunk of the galaxy. But it's constantly fighting various supernatural and alien threats, from both without and within. Because it's been like that for thousands of years by the time this game takes place, and because millennia of warfare have caused a loss of higher learning and higher tech, humanity's slowly going extinct.
-In this game, you play a member of the Ultramarines, a chapter of the Space Marines, the genetically engineered super-soldiers that serve as the greatest fighting force the Imperium has. Your mission? Free the forge world of Graia from the Chaos scum that have invaded it.

Want more information? Then start here: https://wh40k.lexicanum.com/wiki/Main_Page. Either that, or read the Horus Heresy novels, which give a good in-lore historical background on the civil war that directly led to the Imperium being such a messed-up place.

Originally posted by Valden21:

-In this game, you play a member of the Ultramarines, a chapter of the Space Marines, the genetically engineered super-soldiers that serve as the greatest fighting force the Imperium has. Your mission? Free the forge world of Graia from the Chaos scum that have invaded it.

Wrong forum?

Originally posted by SmellofNapalm:

Originally posted by Valden21:

-In this game, you play a member of the Ultramarines, a chapter of the Space Marines, the genetically engineered super-soldiers that serve as the greatest fighting force the Imperium has. Your mission? Free the forge world of Graia from the Chaos scum that have invaded it.

Wrong forum?

To be fair with the amount of carnage we can cause we might as well be space marines.

Originally posted by SmellofNapalm:

Originally posted by Valden21:

-In this game, you play a member of the Ultramarines, a chapter of the Space Marines, the genetically engineered super-soldiers that serve as the greatest fighting force the Imperium has. Your mission? Free the forge world of Graia from the Chaos scum that have invaded it.

Wrong forum?

My bad. I was thinking that I was still in the Boltgun forum.

Necromunda world is interesting to me, aliens and whatever bore me.. (I think they are aliens from the limited i've seen) The necromunda seems super dark and messed up and i dig that hard! I want to learn the warhammer world but dont want to invest years to learn it.. hence my lazy attempt to have someone gloss over it for me xD

Originally posted by Kieora:

Necromunda world is interesting to me, aliens and whatever bore me.. (I think they are aliens from the limited i've seen) The necromunda seems super dark and messed up and i dig that hard! I want to learn the warhammer world but dont want to invest years to learn it.. hence my lazy attempt to have someone gloss over it for me xD

Well, that's not really how this works. Necromunda: Hired Gun is just one part of a really dark sci-fi franchise that's been on-going for at LEAST 40 years. Maybe 50 years. So there's a LOT of lore there, and it's all connected. At the very least, you need to know about the Imperium of Man (https://wh40k.lexicanum.com/wiki/Imperium_of_Man), and the planet of Necromunda (https://wh40k.lexicanum.com/wiki/Necromunda_(planet).

The Emperor wanted 2 unite and save mankind from Chaosgods.
The Emperor failed and now is a rotting yet alive corpse.
The world of Warhammer is his shrine.

Once John Warhammer collects all 40 thousand warhammers, he can bring the Emperor back to life and finally win

Basically things were good and it was a generic sci-fi setting but that was around 30,000 years ago, space elves had weird disgusting snu snu until it formed a new god that became sentient and threw the universe into absolute chaos with demons feeding on emotions of all kinds. people starting getting psychic abilities that the demons like to try to feed off of and the best way to stay alive is to be paranoid and violent.

The super abridged version for Necromunda is that you are on a hive planet, essentially a planet with such a dense population it has turned into one planet, covering mega city that also spans dozens or hundreds of layers in vertical height. The 'Underhive' the game takes place in is essentially the deepest bowels of that mega city, hundreds of meters below a single spec of sunlight. Toxic fumes from the machinery are the least of your worries given these places exist in a state of perpetual lawlessness.

You take the role of a heavily cybernetically enhanced bounty hunter that is tasked with keeping a relative stable balance between the factions following a high-profile assassination that caused a power vacuum every gang is trying to fill and getting dragged into a conspiracy that could affect the hive as a whole.