Black Dragon Darkness Radius (and other dragon issues)

In a couple of places in the SRD (and the MM) certain things are measured in "x per age category". For example with Black Dragons it notes that they have the darkness spell-like ability, and describes it as follows:

juvenile or older; radius 10 feet per age category

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Is that 10 feet per age category starting with wyrmling (such that a juvenile would have a radius of 40 feet) or per age category starting with juvenile (giving a juvenile a radius of 10 feet)?

How do you know this? That is, where might I find it explained? I'm working on a d20 product and I ideally want to get it right "by the rules" as opposed to what makes the most sense to the bulk of folks here (or to me), if possible.

Fast Learner said:

In a couple of places in the SRD (and the MM) certain things are measured in "x per age category". For example with Black Dragons it notes that they have the darkness spell-like ability, and describes it as follows:

Is that 10 feet per age category starting with wyrmling (such that a juvenile would have a radius of 40 feet) or per age category starting with juvenile (giving a juvenile a radius of 10 feet)?

How do you know this? That is, where might I find it explained? I'm working on a d20 product and I ideally want to get it right "by the rules" as opposed to what makes the most sense to the bulk of folks here (or to me), if possible.

Click to expand...

Look at the table entitled Black Dragon Abilities by Age. If you look under special abilities, you will find Darkness listed at Juvenile.

EDIT: Errr, wait, I understand your confusion now. It is 10' per age catagory starting at wyrmling, so when the dragon gets this ability as a juvenile, it has a 40' radius. The reason I am sure of this is because it says "10' radius per age category." If it was the other way, it would say "10' radius per age category minus three." To prove my point I will use the Paladin's turn undead ability. "When a paladin reaches 4th level, she gains the supernatural ability to turn undead. She may use this ability a number of times per day equal to 3+ her Charisma modifier. She turns undead as a cleric of three levels lower would." In other words, paladin level minus 3.

Xarls Taunzund said:

It is 10' per age catagory starting at wyrmling, so when the dragon gets this ability as a juvenile, it has a 40' radius. The reason I am sure of this is because it says "10' radius per age category." If it was the other way, it would say "10' radius per age category minus three." To prove my point I will use the Paladin's turn undead ability. "When a paladin reaches 4th level, she gains the supernatural ability to turn undead. She may use this ability a number of times per day equal to 3+ her Charisma modifier. She turns undead as a cleric of three levels lower would." In other words, paladin level minus 3.

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That's my intuitive and semi-logical take on it, too, but "age category" isn't quite the same thing as "level," which is more like "hit die". Hence my still being a little torn.

Pretty straightforward, the "Dragon Age Categories" table associates a number with each age. Juveline is age category 4, so "radius 10 feet per age category" is 40 feet radius at that age.

Ah, the numbers next to the category, excellent point. Works for me.

Thanks to both of you.