Combination Dust (3.5e Equipment)
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This mnemonic powder gently glows with a mild white light in inert state and is kept in a small jar or a tightly fastened bag. A spellcaster can impart a number of spell levels into a handful of combination dust equal to 5 plus half his caster level (rounded down). It is possible to add both arcane and divine spells to the combination dust, or to have multiple spellcasters contribute to the charging of the combination dust, but the number of spell levels that can so be imparted depend on the caster level of the spellcaster that holds the combination dust in his hand. Imparting a spell in combination dust requires the spell's usual casting time and can only be done if the duration of the spell is not instantaneous and if the range and target of the spell are not 'Personal' and 'You'. Also, summoning spells cannot be imparted in combination dust.
When a handful (1 ounce) of combination dust is thrown, it spreads out in a hemisphere with 30 ft. radius in front of the thrower. The front of the cloud of combination dust will then continue to move away from the thrower at 10 ft. per round until after three rounds the 30 ft. hemisphere becomes a circular area with 30 ft. radius, at which point the whole cloud continues to move away at 10 ft per round until its spell effects are spent. Any creature within the combination dust's area of effect is affected by all the stored spells. All spell effects imbued in the dust are considered to be the effects of one joint spell, and the effective spell level of the combination dust is equal to the number of spell levels imbued (to a maximum of 10). The save DC for all of the combination dust's effects is equal to 10 + the combination dust's effective spell level + the using spellcaster's spellcasting-governing ability score. Every effect still needs an individual save of its intended type.
Duration: The duration of all effects imbedded in combination dust equals the shortest duration of any effect imparted to a minimum of a number of rounds equal to the combination dust's effective spell level.
Adding Spells of Opposite Descriptors: Danger: When one attempts to imbue spells with opposite alignments, elements or charge (such as cure and inflict spells, Good and Evil spells, Lawful and Chaotic spells, spells with the Light and Darkness descriptors, spells that deal cold and fire damage, etc.) the combination dust causes an explosion in a 30 ft. radius, dealing 2d6 raw magical damage for each spell level imbued at the time of explosion (counting both opposite spells). The people surrounding the spellcaster holding the combination dust in his hand may make a Reflex save against a DC of 10 + the number of spell levels imbued to halve the damage done, but the spellcaster himself is not entitled to such a save.
Special: A cloud of combination dust cannot be dispelled by anything less than a mage's disjunction, although all effects are suppressed as normal within the area of an antimagic field. Despite this, a gust of wind spell will disperse the combination dust cloud.