Ok, I get the rules for combining magic items into one item, add half the cost of the lesser effect to the item cost, create as normal. What I'm curious about is how do the magic auras interact? Specifically, I want to add a Prisoners Ring enchantment to a Ring of Protection. So, the RoP is the base item with a weak Abjuration aura. We then add the PR enchantment, which has a moderate Divination aura. Which aura will show up to detect magic, the base item's aura or the stronger secondary aura? If it's the latter as I suspect, how could it be masked without GM fiat?
1st Round: Presence or absence of magical auras.
2nd Round: Number of different magical auras and the power of the most potent aura.
3rd Round: The strength and location of each aura. If the items or creatures bearing the auras are in line of sight, you can make Knowledge (arcana) skill checks to determine the school of magic involved in each. (Make one check per aura: DC 15 + spell level, or 15 + 1/2 caster level for a nonspell effect.) If the aura eminates from a magic item, you can attempt to identify its properties (see Spellcraft).
So, on round two just the most powerful aura, and he doesn't know what school it is, only the power level. On round 3 all auras are visible and can be identified.
If you want to obfuscate the trap, use Magic Aura spell.
@LazerX- not so much a trap as a way for the BBEG to keep an eye on his investment. He's using the PCs as pawns, so he wants them to be useful pawns.
@Claxon- I thought of that, but I was hoping there was an option he wouldn't have to renew every couple of weeks.
@Claxon- I thought of that, but I was hoping there was an option he wouldn't have to renew every couple of weeks.
If you're the DM make it permanent through the Permanency spell. If you're not, ask your GM if you can.
It may be in GM fiat territory but Cursed Item.
Actually, the more I think about it, the more I like the Magic Aura option. For the first couple weeks it'll register like a normal ring of protection. After that, well, who keeps checking the auras of their own magic items? Also, gives one more chance for the PCs to notice he's not the good guy they think he is if they happen to catch him renewing the enchantment. I knew Spellsong would come in handy!