I have come across the knave rules a few times on the internet forums so I downloaded it took a look at it. The rules are written by Ben Milton. The rules are minimalist. The rules check in at only 7 pages and 2 of those pages are spells (and some magic rules).
The rules are written with the intention of allowing you to run OSR adventures with only a few changes. There are a number of minimal rulesets online but these take a different approach. The six standard attributes are still here (called abilities) but they do not modify rolls. Instead, they are used as ability checks whenever a character attempts something. The attributes are also created differently. You roll 3d6 and keep the lowest roll. That number is the bonus and 10 is added to it for the “defense” of the attribute.
There are no classes or class like abilities. Any character could fight, wear armor, pick locks or perform any action.
In a move not unlike a computer game, characters have equipment slots. In this case, based on their CON defense. So if you have a CON of 12 you can have 12 items. That includes worn or held items. Small items like coins fit multiples in a slot (in this case 100). Hit points are d8 based and are re-rolled at each experience level.
Saving throws, which are the basic roll for attempting actions, is a d20 roll with relevant ability bonus. A 15 or greater succeeds. Opposed rolls are a little different, instead, you use the opposing character’s relevant defense. There is the possibility of advantage and disadvantage.
Combat is an old-fashioned d6 initiative for each side. Attack rolls are d20 + STR for melee or WIS for ranged. WIS because I believe they wanted to make every ability relevant. If the attack is greater than the defender armor class it hits. Standard weapon damage is applied. There are a neat weapon and armor quality rules that come into effect on fumbles and critical rolls.
There is a provided option to allow players to make all of the rolls, in other words, attack rolls when on the attack and defense rolls when being attacked.
Healing is d8+ CON bonus after a meal and night’s rest.
The rules suggest that standard OSR Monsters can be used with few changes.
Magic is very different. Spells are cast from spellbooks that must be held in both hands and read aloud. A spell can be cast once per day per book. Each spellbook contains a single spell and takes up 1 equipment slot. This could lead to a lot of high CON mages. Spellbooks must be found. They cannot be transcribed or traded. Spell success is based on the relevant save by the defender so anyone can cast spells.
Would I use these rules? Possibly, I can see that these rules would be great for new players or online games. If I did run it online I would be tempted to allow the players to make all of the rolls so I could concentrate on the world-building. I wonder if all of the characters might not feel about the same. I think it might only be the player personalities that come to the fore.
The rules suggest creating a character using a completely random method for the statistics, equipment, and even the character’s personality. I decide to roll up a character and came up with Oddmantle (below).