System

While it’s based on previous incarnations of d20 role-playing games, the Knaack Hack System has some key differences put in place to help streamline and simplify the overall experience.

Dice and Difficulties

Just about every risky action you attempt will require a d20 modified by whatever attribute and proficiency bonuses apply. The narrator sets the difficulty and, if you meet or exceed this with your roll, you succeed. A roll of natural 20 (20 on the die, regardless of modifiers) is always a success, while a roll of natural 1 is always a failure.

Easy actions have a difficulty of 5, moderate are 10, hard are 15, challenging are 20, and heroic are 25.

Attributes and Proficiencies

For most d20 rolls, you’ll add one of your attributes as a bonus, such as dexterity for walking a narrow ledge or charisma for trying to persuade a city guard to let you pass. You also add your level to all rolls that involve one of your proficiencies and half your level, rounded down, to all other rolls. This is called a proficiency bonus.

Advantage and Disadvantage

Whenever you have advantage, roll the d20 twice and take the higher result. If you have disadvantage, roll twice and take the lower result. Advantages and disadvantages do not stack, but they do cancel each other out.

Helping

If an ally spends an action and makes the same roll as you, they can provide you with advantage on your roll, though the difficulty when doing so is only 10, regardless of what the action is. This works both in and out of combat, though to help an ally in combat, you must be close to them. You cannot use a helping action during a teamwork roll, as you need to spend your action to participate in the teamwork roll itself.

Teamwork

Sometimes, your whole group will need to make the same roll and succeed or fail as team. These are called teamwork rolls, which are most commonly used for initiative. Each character rolls separately, with the highest roll serving as the result for the entire group. Each other character who rolls a 10 or better adds +1 to that result, which each character who rolls below 10 subtracts -1.

Automatic Average

Whenever you’re not in danger and have plenty of time to dedicate to an action, you can choose to take an automatic result of 10 instead of rolling the d20. This works for spellcasting as well, often referred to as “ritual” casting, used to avoid the potential danger of failing or rolling a natural 1.

Advancement

Characters advance - or “level up” - at milestones set by the narrator. Whenever this occurs, you gain additional health based on your class, which you must roll, though you also add your constitution at each level. At every even level, you gain an increase of +1 to an attribute of your choice. At most odd levels, you will receive a new class ability or an improvement to a class ability you already have. The maximum level a character can reach is 10.

Time

Time is broken up into scenes. There's no set size or duration of a scene; they take as long as they need to move the story along. A scene might be a thirty second barroom brawl, an hour-long audience with the king, or even a two-week hike through a snowy mountain pass. Some of the actions a player can take affect them or their surroundings for an entire scene. The narrator decides what goes into a scene, where it takes place, how long it lasts, and what the specific challenges and potential rewards are, then it's up to the players to figure out how they approach it.

Worldbuilding

The Knaack Hack makes a lot of assumptions about the game world you’ll probably be using. Brave heroes explore the depths of long-forgotten ruins while powerful, otherworldly creatures plot to overthrow the world. Kings and queens vie for power, merchant and thieves’ guilds scheme in the shadows, wizards meddle with powers beyond their comprehension. Some of these time-worn tropes date back to the earliest incarnations of fantasy gaming – some even further.

While these standard fantasy world assumptions can easily paint a fully functional realm for players to explore, narrators are encouraged to add their own unique touches. Maybe all spellcasters are hunted by a cult, most labor has been replaced by steam power, and dragons are the benign protectors of the realm. Interesting things can happen simply by flipping some of these tropes. The only rule is: There are no rules!

Rule Zero

Though RPGs claim to be made up of strict rules and carefully-balanced abilities, everything you read here is really just an elaborate, organized list of helpful suggestions and purely optional statistics. Rule Zero of any RPG is that you can follow, change, or even ignore any rule that would detract from the fun of your game, so feel free to take your own red pen to this guide!

Rulings Instead of Rules

One of the most important things to remember as you read this book, and especially as you narrate the game, is that this by no means a complete list of all the rules. If you notice any gaps, that means it’s up to you to improvise, filling in the blanks with your own judgment and rulings. Likewise, you should feel free to expand on the content given here, adding races, classes, equipment, spells, monsters, or treasure as desired, tailoring each area to fit your game. Not only can such customization bring your world to life, but it can serve as a constant source of wonder and surprise for your players!