Comparing Dice Systems in RPGs: The Benefits of Using 3d6 Instead of 1d20

In tabletop role-playing games (RPGs), the mechanics of dice rolling are central to the gameplay, influencing everything from character actions to success in combat. While the 1d20 system—rolling a single 20-sided die—is popularized by games like Dungeons & Dragons, an alternative system involves rolling three six-sided dice (3d6). This method presents distinct statistical and gameplay advantages that can significantly alter the gaming experience, promoting a more predictable and controlled environment.

Statistical Predictability and Reduced Variance

A Closer Look at the Bell Curve

The primary advantage of a 3d6 system is its statistical behavior, which follows a bell curve distribution. Unlike the flat probability distribution of a 1d20 roll, where each outcome from 1 to 20 has an equal 5% chance of occurring, the 3d6 system clusters results around the median value (10 or 11). This means that extreme results (both low and high) are less common, making the game outcomes more predictable and allowing players and Game Masters (GMs) to plan with greater precision.

Impact on Gameplay Consistency

This predictability enhances gameplay consistency. Players can expect more regular outcomes from their actions, reducing the frustration of random failures and the unpredictability that can sometimes make a 1d20-based game feel capricious or unfairly penalizing. The 3d6 system lends itself to a style of play where strategy and character skills play a more significant role than chance, appealing to players who enjoy tactical depth and thoughtful planning.

Enhanced Role-Playing and Character Development

Smoothing Character Progression

The 3d6 system also affects character development and progression. Because the system reduces the likelihood of extremely high or low rolls, it tends to highlight the character's skills and abilities over the randomness of the die. This can make character growth feel more meaningful and impactful, as players see a more direct correlation between their characters' abilities and the outcomes of their actions.



Balancing Challenges and Encounters

For GMs, the predictability of the 3d6 system makes it easier to design balanced challenges that are appropriately scaled to the party's abilities. Encounters can be tailored to be challenging yet fair, with less risk of an unexpected die roll completely altering the course of an event. This can lead to a more satisfying narrative progression and a smoother overall gameplay experience.

While the 1d20 system has its charms, particularly in its simplicity and the dramatic tension it can generate with its wide range of outcomes, the 3d6 system offers compelling advantages for those seeking a more controlled and predictable RPG experience. By reducing randomness, enhancing strategic planning, and fostering a closer alignment between character development and game outcomes, the 3d6 system can provide a deeply satisfying and tactically rich gaming environment.

Switching to a 3d6 system might be worth considering if your gaming group prefers a game where strategy outweighs luck, and every roll adds meaningfully to the story you're collectively creating. Crusaders TTRPG has decided to switch to the 3d6 system as it makes balancing the game for modular dungeon master experience easier.