Hi everyone!

I'm new to this community and relatively new to game design as well. I'm a young designer from Brazil working on this project alongside a friend, and we'd love to get some feedback from experienced creators here.
Our goal is to build a genre-agnostic / universal RPG system that can easily adapt to any setting—whether it’s grounded realism, high fantasy, mystery, cosmic horror, or anything in between.
We are currently looking for feedback on two main aspects:
Rulebook Structure & Organization: Is the information presented logically and clearly for a new player or Game Master?
Core Dice Mechanics & Resolution System: Does the core roll mechanic feel smooth, intuitive, and adaptable across different genres?
Any thoughts, critiques, or suggestions are greatly appreciated. Thanks in advance for taking the time to check it out!

(Also, the book is originally written in Brazilian Portuguese, so there may be some errors when translating it into English. Thank you for your understanding!)

One more addendum: the book isn’t finished yet (not even close, actually), but my friend and I would like some feedback to know whether it’s worth continuing the project or not. So there are some mentions in the submitted chapters (0 and 1) that don’t actually exist yet.

Chapter 0 - Introduction

What is the ROG System?

The ROG System is a Brazilian TTRPG system designed to be completely modular and adaptable, with no rules or mechanics limiting the Game Master's creativity.

This book is envisioned as a foundation to be modified by the GM, aiming to empower their imagination. However, it is fully playable right out of the box, including optional modules.

Something that might feel unusual is that this book contains no story or lore. Since it is a purely mechanical rulebook, our goal is for it to adapt to your stories, rather than forcing your stories to adapt to the system.

How to use this book:

Throughout your reading, you will come across the following highlighted phrases:

• [may vary depending on the ROG] indicating that a specific section is entirely alterable or removable without any issues.
• [essential mechanic] indicating that a section is part of the core mechanics, and modifying it will be more difficult, requiring a deeper manipulation of mechanics scattered throughout the book.

Still thinking in terms of modification, we want the book to be completely modular, as mentioned above. With that in mind, all essential mechanics have their connections mapped out at the end of the book in the "Mapping" chapter, making it easier to manipulate mechanics that are deeply tied to the system.

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Chapter 1: Basic Mechanics

Every RPG requires mechanics to keep it from becoming an unfair game of make-believe. Without rules, decisions turn into arguments. Every system resolves this in its own way, usually aligned with its core theme.

The ROG System has no central theme. It was designed to adapt to any genre, tone, or setting. For this reason, the mechanics in this chapter do not serve a single playstyle; they serve as a starting point for any game.

Here you will learn how the system resolves uncertain actions: how to roll, how to read the dice, how to compare results, and how the Game Master can customize everything for their table.

[essential mechanic] The rules in this chapter form the bedrock of the entire system. They can be modified or even replaced with some effort if the GM wishes to create a custom variant. However, replacing them requires reviewing all dependent chapters. Before altering anything here, consult Chapter 9 - Connections.

1. Basic Mechanics - Dice Rolls

Every uncertain action in the ROG System is resolved with a dice roll. Every roll relies on four fundamental pillars: two define what your character is capable of doing, and two define how difficult the challenge is.

On the character's side:

• Attribute: Your character's raw capacity to perform the action. In-game: Defines how many dice you roll.
• Skill: Your character's efficiency and training. In-game: Defines the size of dice you roll.

On the challenge's side:

• Resistance: The effort required to complete the action, or the target's defense preventing it. In-game: Defines how many Successes you need to obtain.
• Complexity: How demanding each individual attempt is. In-game: Defines the minimum value each die must hit to count as a Success.

Example:

A character attempts to pick a reinforced lock.

• Body (Attribute) 4: 4 dice.
• Crime (Skill) 3: d8 dice size.
• Resistance 2: Needs 2 Successes.
• Complexity 5: Each die needs a 5 or higher.

Roll: 4d8 : [7, 3, 5, 8]

• 7 : Success
• 3 : Failure
• 5 : Success
• 8 : Success

Total: 3 Successes. Since 3 is greater than or equal to 2, the character picks the lock.

2. Basic Mechanics - Reading Results

To resolve a Check, the player does not need to memorize complex math. They only need to evaluate two elements in order: first Complexity (what each individual die is worth), and then Resistance (what the overall action achieved).

Step 1: Reading the Dice (Complexity)

Complexity dictates what each individual die represents. It yields only three possible outcomes:

• Failure: The die generates 0 successes (result below Complexity).
• Success: The die generates 1 success (result equal to or above Complexity).
• Double Success: The die generates 2 successes (result equal to or above 150% of Complexity, rounded up).

Step 2: Reading the Action (Resistance)

After rolling all dice and tallying the total Successes, the player compares this total against the Resistance set by the GM. This is where the overall action is judged, resulting in 5 possible Conclusions:

• Critical Failure (25% Resistance or less): Something goes terribly wrong. In addition to failing, you suffer an immediate negative consequence. The lockpick breaks, the noise alerts guards, the rope snaps. The GM describes the disaster.
• Failure (more than 25% and up to 50% Resistance): You simply cannot do it. The action fails, but without catastrophic consequences. The door remains locked, the guard remains unconvinced, the jump comes up short.
• Partial Success (more than 50% and less than 100% Resistance): You partially succeed, but at a cost, delay, or complication. The door opens, but leaves noticeable marks. You convince the guard, but they keep a close eye on you. This is the system's most narrative outcome—the classic "you succeed, but...".
• Success (100% to 149% Resistance): You succeed. The action works as intended with no extra costs. The door opens smoothly. The guard lets you pass. The jump is landed cleanly.
• Critical Success (150% Resistance or more): You succeed with mastery. The outcome is better than expected. Beyond opening the door, you find something useful on the other side. Beyond convincing the guard, they become your ally.

Full Example:

A character attempts to pick a lock with Body 4 and Crime 3 (d8). The GM sets Complexity 4 and Resistance 3.

Roll: 4d8 : [3, 4, 6, 1]

• Step 1 (Complexity 4):
  • 3 and 1 are Failures.
  • 4 is 1 Success.
  • 6 is 2 Successes (since 6+ yields Double Success at Complexity 4).
  • Total: 3 Successes.
• Step 2 (Resistance 3): The player obtained 3 Successes and needed 3. Since 3 is exactly 100% of Resistance, the result is a Success. The door opens cleanly.

[may vary depending on the ROG] The GM can adjust the Resistance percentages (25%, 50%, 100%, 150%) or Complexity thresholds to make the game more lethal or more heroic. Consult Chapter 9 - Connections.