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Poppa_Smurf
2010-12-12, 06:38 PM
Hey!

So amongst my many projects I am, at the moment, trying to put together a gaming system that strikes a balance between quite granular RPG systems, like 3.5, and simpler ones like d20lite and the d6 system.

I am trying to understand how more complex systems "balance" everything at a sort of base level, and it occured to me that most are dictated by quite black-letter mathematical rules - e.g. arithmetic progressions.

What I wanted to ask was whether anone had any insight or resources regarding the maths behind successful gaming systems? I'd be interested to see how certain things scaled with regards level progression, or how base damage was related to maximumk damage for different classes etc.

For instance, how the total damage a character can cause in expending all their resources (incl. consumables like potions and healing spells) relates to their level - or how a "stun" or "trip" relates to causing x amount of damage, given that a "stun" or "trip" both prevents an enemy from causing damage and might make it easier for the player to cause damage.

GoodbyeSoberDay
2010-12-12, 09:30 PM
Short answer:
Complex systems don't balance very well.

Long answer:
The fact that you're thinking about this at all puts you above many popular game designers, who think "oh, that's a neat ability" and write it in without much thought to how it would work within the game.

Systems oriented around balance and/or simplicity often use a central mechanic (like a d20) to resolve most issues and make most abilities, advantages and disadvantages isomorphic to bonuses and penalties to that mechanic. Once any advantage and disadvantage can mechanically be described as something which is directly translatable to a modifier to your central mechanic, and you can gauge how often someone is able to have this advantage and what it costs, you can balance each modifier by looking at its expected benefit and its expected cost, all else equal.

For instance, in D&D 4e, the stun effect prevents the target from taking actions and grants combat advantage. Combat advantage grants a +2 modifier to attack, but it also triggers some character-specific abilities; whether you want to assume the stun is used to full effect or not depends on how you think the system will be played. The fact that the enemy cannot take actions decreases its ability to damage or hamper the heroes, but in 4e that effect is felt the most if the stun targets an elite or a solo. How often will the DM throw elite and solo-heavy encounters at the party, knowing such encounters are vulnerable to stun?

Obviously, designing a balanced system isn't the easiest thing in the world. Maybe I was a bit cynical when describing 'some game designers', because even if they did think about game balance implications, they might not have been able to do the math properly, or predict the right combination of abilities (some things, though, have no excuse). The best way to figure out what works and what doesn't is extensive playtesting, which is costly and time-consuming.

The Big Dice
2010-12-12, 09:52 PM
Short answer:
Complex systems don't balance very well.
That really does depend on the complex system. Something that's based on random collections of abilities, in the way D&D is, isn't going to balance well.

But something that's balanced on mathematical formulas, like GURPS, tends to balance better and tends to be harder to break accidentally.