Good morning ladies and gents.
I have a particular fondness for custom magic items in my campaigns, and generally speaking I tend to prefer to have fewer items overall but to compensate by having them be more powerful and/or versatile. As a result, I rarely factor any sort of multipliers in for an item being 'slotless' or having multiple abilities in one - its unheard of that they would get so many items that they would have to pick and choose which thing should take up their head slot or boot slot, so why worry about that? Apart from consumables like potions, scrolls and wands, its rare for magic items to be available for purchase in my campaigns. Likewise, I ignore penalties for narrow or specific activation requirements since the items are still obviously intended for use by my PC's.
Having said all of that, one of the way I combat the banality of constantly buying and selling magical items in order to 'upgrade' is by creating progressive magic items (which I call 'Legacy Items'), items which increase in power as the character levels up. Now, with the understanding that Pathfinder incorporates the benefits of magic items into character strength when determining CR I'd like to keep the benefits of magical gear still relatively balanced as much as possible. For most things I just break them down (like if a set of robes grants both armor bonus to AC and resistance bonus to saving throws, I treat it as a similarly powerful set of armor and cloak separately in my calculations), but many of the items aren't that easy to delineate and I'm struggling to figure out how I might go about determining their value - again, not for sale purposes but with regards to character balance.
I'm going to include some of those custom items below to give you an idea of what I mean, not necessarily in the hopes of determining specific values for these items, but rather in an effort to get a sense of HOW I should go about valuing such items in general. It might require a new approach, like deciding an item is worth X% of a character's gp allotment rather than a specific number (for instance). Any thoughts or suggestions are welcome when it comes to this what feels like an inexact science.
Desna’s Grace:
A holy symbol fashioned of gold and silver that resembles a butterfly alighting on a starknife as if a flower. If the bearer is a worshipper of Desna in good standing, they gain a +1 sacred bonus to AC and to all saving throws. They may also cast Guidance as a spell-like ability 3/day; if they are already able to cast Guidance, then the competence bonus they gain from its casting increases to +2.
Legacy Item: Once ‘activated’ by an event that takes place in the campaign, Desna’s Grace becomes a legacy item - the sacred bonuses to AC and saving throws increase by +1 @ 4th level and every 4 character levels thereafter. Additionally, the bearer will be the beneficent of a Breath of Life spell automatically triggered as an immediate action should they take enough damage to be slain. This ability will work once and thereafter can only be recharged through the completion of a Quest or through the use of a Miracle spell cast by a worshipper of Desna.
Silversliver
A small-sized +1 mithril silver rapier.
Legacy Item: When wielded by a halfling who also a second son of the Silversliver bloodline, the weapon gains the following abilities:
The weapon's enhancement bonus increases by +1 @ 5th level and every five character levels thereafter to a maximum of +5 @ 20th level.
Starting at 5th level, the character may add the weapon's enhancement bonus to Acrobatics & Escape Artist checks as well as Intimidate checks made to Demoralize a foe.
At 10th level, attacks by the Silversliver deal an additional +2 damage to a target for every size level it is larger than the wielder.
At 15th level, the bearer is affected as if under the effect of a continual Freedom of Movement spell.
Boots of the Alacritous Step
These finely appointed boots normally perform as Boots of Striding and Springing.
Legacy Item: at 2nd level, these boots grant the wearer the Dodge feat. At 6th level they gain the Mobility feat. At 10th level they gain the Spring Attack feat. Starting at 14th level the wearer may spend a move action to teleport a distance of up to 30' and at 18th level they may use this ability as a Swift action.
Ring of the Inner Fire
This ring acts as a Ring of Fire Resistance, granting Fire Resistance X where X is the character's level.
Legacy Item: If the bearer is capable of casting arcane spells, they may make a 30' ranged touch attack as a standard action. The attack deals 1d6 fire damage per level of the highest level spell the character is currently capable of casting. If a character has exhausted all of his spells of that level, the attack deals damage equivalent to the next highest level spell they are capable of casting. If a character has an ability or a class feature that increases the damage of fire spells that they are capable of casting (such as the Bloodline Mutation 'Blood Havoc'), they may apply that increase to this attack as well.
Book of Infinite Spell Knowledge
Legacy Item: This book functions as a Page of Spell Knowledge, except that it grants one additional spell known of each level the character is capable of casting. Once per day with an hour of study, the reader may change one of the spells it grants to another spell of the same level or lower.
Those examples should serve as a fair sampling of what I'm talking about; some Legacy items are based on character level, some on other things. Again, any thoughts on pricing approaches in general or on these particular items in particular would be welcome. I'm just trying to make certain that I'm keeping characters balanced both in relation to the encounters presented as well as to each other. Thanks again!
(If Mods/anyone thinks that this post would be more appropriate in the Advice Forum, please feel free to relocate it!)