Basic Fantasy offers a simple optional rule for ability rolls that uses the ability modifier on a d20 roll with a target number set by the character's level of experience. It can be used for any skill, and ability checks that may come up during play.
Example: Klyth wants to climb a tree to collect apples. She's a level 3 cleric so her target number for any such rolls is 16. The GM decides she may apply her Dexterity modifier (+1) to the task. The player rolls 1d20+1, and needs a result of 16, or better to succeed. Now, since the tree seems easy to climb, the GM decides that the ability roll is necessary only to reach some of the apples high up. Klyth plays it safe, and collects some apples from the lower branches, then moves on to gather some kindling.
The GM may apply additional modifiers based on the situation, and character background. And this leads to the description of secondary skills.
Secondary skills are not related to the character class. They represent a character's profession, interests, and education. They may support class abilities, but they are not exclusive to character classes.
Writing the supplement I focused on two aspects:
- Secondary skills integrate seamlessly into the core rules.
- Secondary skills make use of the existing ability rolls.
Skill Levels and Modifiers
There are only five levels for secondary skills: beginner (b), advanced (ad), expert (e), master (m), and grand master (g).
When I wrote the Tiny Skill Companion, I thought about the skill level modifiers, and decided to use a segment of the Fibonacci sequence 3, 5, 8, 13, 21: Beginners (b, +3), advanced (ad, +5), expert (e, +8), master (m, +13), and grand master (g, +21.)
Side note: Among other stuff, I practice improvising melodic phrases on the electric guitar based on Fibonacci sequences. First playing one note, then two, then three, then five, then eight, and so on. I feel that these sequences challenge focusing on melodic phrases better than playing phrases of two, then four, then six, then eight notes.
Anyway, I used them for the skill modifiers, and for other supplements I wrote, as well. For example: the pain thresholds of the &Pain companion expansion are 5/8/13.
Example: If Klyth had the secondary skill climbing (ad, +5), or any other that included climbing the player would add the modifier to the roll: 1d20+5 with a target of 16. The GM may allow to include the Dexterity modifier, too.
Secondary skills add a little more depth to characters, and help the players to make choices within the game based upon these skills. That's why we use them as house rules for Basic Fantasy.