Correct my math!

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Username17
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Correct my math!

Post by Username17 »

Here's your favorite part of game design: Statistics!

The basic mechanic of a mental attack (or any attack) is that you roll an attack roll, and if you hit, for every two points you roll over your to-hit DC you add one to the damage value. Then, your opponent rolls a soak roll against a DC equal to the damage value, and for every two points they miss the roll by, they suffer a point of damage. For every point you add to Intelligence, you add one to your attack roll in a mental attack, for every point you add to Charisma, you add one to the effect level of your mental attack (or to-hit DC/ soak roll if you are on the receiving end).

So if you add one point to your intelligence, you have a 1 in 20 chance of hitting when you otherwise would not have. In addition, you have a 50% chance on any attack that would have been a hit of adding one point of damage, which in turn has a 50% chance of adding one to the effect level of your attack. If you add one point to your Charisma, you have a 50% chance of inflicting an extra effect level times your chance to hit (minus the chance of your opponent rolling such a good soak roll that you wouldn't do any effect level anyway since you can't do negative effects on people by sucking too much).

So how do we balance that? There are a number of balance points in which they statistically have the same effect, but so far I stopped after deriving one of them: the simplest case when the vast majority of strikes inflict damage.

If the base to-hit DC then is 3, and the base damage DC then is 19, the two stats are balanced. Every attack hits 90% of the time, and has an average overdamge per hit of 4. Therefore the average hit on an enemy jumps the damage DC up to 23 and causes about six and a half effect levels on average.

Adding 1 to Int gives a 1/20 chance of inflicting the average damage with no overdamage (4.5 effect levels), as well as a 1/4 chance of inflicting an extra effect level on any attack that would have hit anyway (90% chance). So that's a 5% chance of 4.5 effect levels and a 90% chance of 1/4 of an effect level - for a total of .45 average effect levels.

Adding 1 to Charisma gives a 50% chance of an effect level on any attack that would have hit anyway (90% chance) - which is again a .45 average jump in effect levels.

Is that too fast and furious, or about right?

-Username17
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Sir Neil
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Re: Correct my math!

Post by Sir Neil »

It appears to be neither 2 Fast, nor 2 Furious. I've played with a lot of newbies, and they like to hit things. If they go to long without hitting, they get frustrated and go to sleep.
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