Spell-Like Engine (3.5e Equipment)

Spell-Like Engine
''This chestpiece has a crystal embedded in the center. When using your spell-like abilities, it glows with an eldritch light.''

A spell-like engine increases the number of times you can use a pre-existing spell-like ability you know. The spell-like engine is attuned to one or more specific spell-like abilities (such as the tiefling's darkness 1/day), and grants more uses of it. The cost to increase a spell-like ability is spell level squared x additional times per day x 2500 gp. For example, gaining two additional uses of darkness on the tiefling (for a total of 3/day) is 1 x 2 x 2500, or 5000 gp.

If you reach 6/day, the ability instead becomes at will. Going from a 9th level spell 1/day to at will would be 9 x 5 x 2500, or 1,012,500 gp.

You must wear the spell-like engine for 24 hours to attune to it before using. You may also swap which spell-like abilities benefit from the spell-like engine for spell-like abilities of the same level over 24 hours. For example, you can change a spell-like engine which benefits darkness +3/day and fireball +1/day to instead benefit magic missile +3/day and lightning bolt +1/day.

Prerequisites: Craft Wondrous Item, imbue with spell ability.

Cost to Create: 1/2 Market Price, 1/25th Market Price in EXP, 1 day per 1,000 gp in the base price, minimum of 1 day.