So, i originally posted this in the general gaming forum. I realize that this is probably the more appropriate spot for it.

OK, so I'm playing a True Necromancer. There are not a lot of good qualities about the True Necromancer class, so I want to maximize the things that are. My first thought is to improve on the Desecrate aura that he has. I want to make an item that will, mechanically, act as a shrine to an evil god in regard to the Desecrate spell. That will effectively double the effects of my aura while the item is present. I'd like it to be something wearable, like a cloak or belt. I just have no idea where to start with pricing a "mobile shrine."

The effects of the aura are as the spell Desecrate (see below). Essentially, turning checks in the area would suffer another -3 penalty and all undead in my aura would gain an additional +1 profane bonus to hit and +1 hp / HD.

Any thoughts?

Spoiler
Show

Quote Originally Posted by SRD
Desecrate
Evocation [Evil]
Level: Clr 2, Evil 2
Components: V, S, M, DF
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Area: 20-ft.-radius emanation
Duration: 2 hours/level
Saving Throw: None
Spell Resistance: Yes
This spell imbues an area with negative energy. Each Charisma check made to turn undead within this area takes a –3 profane penalty, and every undead creature entering a desecrated area gains a +1 profane bonus on attack rolls, damage rolls, and saving throws. An undead creature created within or summoned into such an area gains +1 hit points per HD.
If the desecrated area contains an altar, shrine, or other permanent fixture dedicated to your deity or aligned higher power, the modifiers given above are doubled (–6 profane penalty on turning checks, +2 profane bonus and +2 hit points per HD for undead in the area).
Furthermore, anyone who casts animate dead within this area may create as many as double the normal amount of undead (that is, 4 HD per caster level rather than 2 HD per caster level).
If the area contains an altar, shrine, or other permanent fixture of a deity, pantheon, or higher power other than your patron, the desecrate spell instead curses the area, cutting off its connection with the associated deity or power. This secondary function, if used, does not also grant the bonuses and penalties relating to undead, as given above.
Desecrate counters and dispels consecrate.
Material Component: A vial of unholy water and 25 gp worth (5 pounds) of silver dust, all of which must be sprinkled around the area.


Edit: I've just found an item called a Darkskull in the DMG. It's a skull that effectively has a permanent Unhallow effect on it (with minor adjustments). First, would you rule that this item would count for doubling the aura? Second, if the answer is no, would it at least be a decent base to start with?

Spoiler
Show

Quote Originally Posted by SRD
Darkskull: This skull, carved from ebony, is wholly evil. Wherever the skull goes, the area around it is treated as though an unhallow spell had been cast with the skull as the touched point of origin (except that no additional spell effect is tied or fixed to the darkskull).
Moderate evocation [evil]; CL 9th; Craft Wondrous Item, unhallow, creator must be evil; Price 60,000 gp;Weight 5 lb.


Spoiler
Show

Quote Originally Posted by SRD
Unhallow
Evocation [Evil]
Level: Clr 5, Drd 5
Components: V, S, M
Casting Time: 24 hours
Range: Touch
Area: 40-ft. radius emanating from the touched point
Duration: Instantaneous
Saving Throw: See text
Spell Resistance: See text
Unhallow makes a particular site, building, or structure an unholy site. This has three major effects.
First, the site or structure is guarded by a magic circle against good effect.
Second, all turning checks made to turn undead take a –4 penalty, and turning checks to rebuke undead gain a +4 profane bonus. Spell resistance does not apply to this effect. (This provision does not apply to the druid version of the spell.)
Finally, you may choose to fix a single spell effect to the unhallowed site. The spell effect lasts for one year and functions throughout the entire site, regardless of its normal duration and area or effect. You may designate whether the effect applies to all creatures, creatures that share your faith or alignment, or creatures that adhere to another faith or alignment. At the end of the year, the chosen effect lapses, but it can be renewed or replaced simply by casting unhallow again.
Spell effects that may be tied to an unhallowed site include aid, bane, bless, cause fear, darkness, daylight, death ward, deeper darkness, detect magic, detect good, dimensional anchor, discern lies, dispel magic, endure elements, freedom of movement, invisibility purge, protection from energy, remove fear, resist energy, silence, tongues, and zone of truth.
Saving throws and spell resistance might apply to these spells’ effects. (See the individual spell descriptions for details.)
An area can receive only one unhallow spell (and its associated spell effect) at a time.
Unhallow counters but does not dispel hallow.
Material Component: Herbs, oils, and incense worth at least 1,000 gp, plus 1,000 gp per level of the spell to be tied to the unhallowed area.