With so many converting material from their d6 and d20 games to the Star Frontiers d100 system, and with so many in the d20 games that could benefit from the material in the Star Frontiersman, I thought I would provide an easy conversion system for converting material to and from the d20 system.

Why a Conversion and Why d20?
This is not just a conversion to one or the other system. This is a cross-conversion, meaning it converts materials both ways.

The reason this is needed is because there is lots of material in the d20 system that would work great in Star Frontiers. There's also a lot of material in the Star Frontiers books, magazine, and starfrontiers.us web site that would be much desired in d20 games. It would be of particular help to the alienated fans of d20 Future who feel their game has been abandoned to its own devices by WOTC. d20 future was primarily based on the Alternity: StarDrive, Gamma Dawn, and Star Frontiers settings.

Such cross-conversion provides cross-pollination, expanding the player base of Star Frontiers and visitors to the starfrontiers.us site as well as expanding the well of material that players of both game systems can draw from, and allowing the d20 community to benefit from reading the Star Frontiersman webzine.

The Core Mechanics
The Star Frontiers d100 game system resolves all actions with percentile (d100) dice. To determine if your character succeeds at a task (such as an attack or the use of a skill), you do this:

• Add any relevant modifiers to a target number itself.

• Roll a d100.

• Compare the die roll result to the modified target number.

If the result is equal to or less than the modified target number, your character succeeds. If the result exceeds the modified target number, you fail.

Conversely, in the d20 game system, whenever you attempt an action that has some chance of failure, you roll a twenty-sided die (d20). To determine if your character succeeds at a task (such as an attack or the use of a skill), you do this:

• Roll a d20.

• Add any relevant modifiers to the die roll.

• Compare the modified die roll result to a target number.

If the modified result equals or exceeds the target number, your character succeeds. If the modified result is lower than the target number, you fail.

If you will notice, there are two fundamental deferences between these two systems:

1) In d100, you want a lower roll, while in the d20 system, you're shooting for a higher roll.

2) As a result of the above difference, in the d100 system, you apply the modifiers to the target number, but in the d20 system, you apply the modifiers to the die roll instead.

The Dice
10-sided dice are nothing new to the d20 system, but the multitude of dice shapes in d20 are totally foreign to the Star Frontiers d100 system.

Because of this, many tables must be carefully compared and translated.