Mechanics
Kanna has five stats.
Organize: 3
Optimize: 4
Precaution: 2
Speechify: 3
Magic: 5
When attempting an action, she uses the most relevant stat. If you attempt an action that doesn't fit any of the stats at a stretch, you will roll 1d10. If you attempt an action that is especially suited to a synergistic approach (such as 'Optimize Magic' for making an airship more efficient), she adds two stats together and rolls the total.
After rolling, any die above a certain threshold counts as a success. The threshold depends on the difficulty.
3: Routine (I.E. cleaning cantrips)
5: Simple (I.E. construction via telekinesis)
7: Complicated (I.E. hand-build a mana motor)
9: Fiendish (I.E. complicated magic shields)
10: Cutting Edge (I.E. teleportation, portals, etc)
As far as chances of success at difficulties 3/5/7/9/10 go, the chance for at least 1 success are as follows:
At 2 dice (weak) that's 96/84/64/36/19%
At 3 dice (average) that's 99/94/78/49/27%
At 4 dice (strong) that's ~100/97/87/59/34%
At 5 dice (excellent) that's ~100/99/92/67/41%
Extra successes make the result more dramatic, but two successes is not necessarily exactly twice as good as one.
Rolling 10s adds extra dice- One for each 10 rolled. Since 10 is the hardest difficulty, these also automatically count as 1 success.
Rolling 1s subtracts one success for every TWO 1s rolled. If the final result has a negative number of successes, it's a critical failure with dramatic negative results
EXAMPLES:
Kanna wants to sort through some paperwork and figure out how much supplies an army has available. This action seems pretty applicable to Organize, which is scored at 3.
Scenario 1:
This particular portion of the army has a dedicated and well-organized logistical corps that keeps the paperwork in good order. Difficulty: 4. Not quite routine, but still easy.
She rolls: 8, 2, 4. Two successes! She gains an excellent picture of the supply situation and even thinks of ways to extend it a little bit, perhaps new routes to get supplies faster or ways to reduce wastage.
Scenario 2:
The reports were made by unmotivated conscripts so the papers are confusing, but at least she's familiar with the jargon. Difficulty: 6. Tricky, but far from impossible.
She rolls: 10, 9, 1, and an extra die: Another 1. What rotten luck! The extra die rolled a 1 and took us from two successes down to one. Still, one success means that she does manage to understand the current supply status.
Scenario 3:
The paperwork is a mess, and worse, she's not great at the language yet. This makes it very difficult to get things done. Difficulty: 8. Ugh, what a mess…
She rolls: 5, 6, 7. No successes. But not a terrible failure either. The result is simply that she makes little progress on understanding thanks to language issues.
Scenario 4:
Kanna wants to make her favorite shield spell even more efficient. It's already very, very good, so making any further improvements is quite difficult. This is cutting edge stuff! Difficulty is 10. However, her Optimize plus her Magic is 9 dice! With that many rolls, surely it'll work well?
2, 1, 3, 4, 7, 8, 5, 6, 8
Alas! No successes. Even with her prodigal skill at optimizing magic, this task was simply too difficult to always succeed at. If she'd rolled two ones, though… Perhaps she would have failed to notice a fatal flaw in the new design until it was too late.