Mörk Borg according to a Swedish friend means Dark Fortress.
I played a game of this during a convention and loved it enough to buy a copy of it.
Minimal OSR (Old School Renaissance) RPG. Heavy Metal album cover aesthetics such as Iron Maiden make up the interior and exterior art. Back of the book states that it's not appropriate for anyone under 16 years old. The rules for playing is only one page. The digest size book is full of very flavorful random charts for character creation, Psalms, spell fumbles, looting bodies, etc.
The GM doesn't really roll any dice. The PCs roll attack and defense dice. Most target numbers are 12+ on a 1d20. You can either go by Individual Initiative or by Group (either PCs or Monsters go first, 50/50). Basically rolling high is good for the PCs in this game, so use that as a rule of thumb. If doing a 50/50 roll, just rule that a high roll is good, low is bad. Natural 1s are Fumbles, Natural 20s are Crits. PC Hit Points are low (1-11). Reach negative HPs and you're dead. If you're lucky enough to hit 0 HP exactly, you're Broken and there's a chart for that (p.29).
Since the rules are very minimal and you have to read between the lines to figure things out, you need to house rule a lot of things too. What the book provides is inspiration.
The best thing since sliced bread is the random character generator: https://scvmbirther.makedatanotlore.dev/
My first character was an Occult Herbmaster. If you read his decoctions carefully (reading between the lines), you can figure out what he really is. When I dispensed Hyphos' Enervating Snuff, I taught a PC in its proper ritual use; you must pour the snuff on a small mirror, chop up the powder into white lines, pinch one of your nostrils, and snort the powder up your nose. Ezumiels Vapor needs to be inhaled.
The first thing I do as a GM is call the party members a Band such as a Band of Brothers or jokingly, a Heavy Metal Band. And the Players have to name their Band. I tell them the Band name is three heavy metal themed words. You can have different Players come up with each word. Examples are: Death Murder Puppies, Black Storm Reaper. Feel free to veto any word that isn't Metal enough.
Next, tell them their Band is a large group of survivors. Random people with followers, carts, wagons, animals, all their belongings. This could be 20 to 40 people. This is their reserve of backup PCs. Since survival is so hard, they basically do nothing but survive and only step up to full PC-hood when a PC dies.
The Apocalypse is happening. It's not post-apocalyptic, because there's no post. When the Apocalypse happens, the world ends. Period. For one-shots, I'd have them roll 3 random Miseries from p.17 and say they've already come to pass. The Miseries sound like Biblical prophesies. The seventh Misery is always the end of the world. The Miseries are up to GM interpretation and any input from the Players are welcome. For example: "1:5 Doubt is crowned. The loyal shall turn their blades on those who silver gave." I decided that silver is now cursed. If you give anyone silver coins, they will immediately attack you. The Miseries should be big world affecting events or effects that cannot be ignored.
For a non-one-shot, I'd go with the The Calendar of Nechrubel (p.16). Start with zero Miseries, roll each day to see if one occurs.
I'd also look at Getting Better or Worse p.33. Letting PCs "Level Up" will add 1d6 in HP which would greatly increase the chance of a starter character surviving.
So, what is this game about? I think that's up to the GM and Players. I'd think it'll be about doing something meaningful before it all ends. One option is to try to stop the Apocalypse. Another is to finish any unfinished business the PCs have. Another is to try to survive as long as possible.
For one-shots, there are a number of one page dungeons available online. The best ones put some sort of curse on the PCs and they must adventure in order to throw off the curse.
In D&D, the stereotypical PC is a murder hobo, so in Mörk Borg, there's a Corpse Plundering table (inside cover). It's full of random inspiration, some useful stuff, mostly horrible. When my Players plundered some corpses, they found silver (useless in this case, due to the curse) and A hopeless amount of spiders. 😊
Included is a one page dungeon: Rot Black Sludge. Review is below.
There are also random tables for generating Dungeons and Adventures (last few pages).
Overall, a fun and evocative game of dark fantasy.
