Spellmines (3.5 item)
The idea came from my warmage rebuild, but I figure I'll get more and better feedback if I post it separately. Not to mention that some people might like to use spellmines independently from that class.
The basic idea is magically-crafted mines/grenades. They're basically an adaptation of potion rules/pricing.
Spellmine- A spellmine is a magical booby-trap, a spell waiting to be unleashed on the first person who passes by. Any spell up to third level can be stored in a spellmine. A spellmine is typically buried under a shallow layer of earth, but can be crafted to blend into the landscape. The spell is triggered by any solid impact, such as being stepped on or thrown sharply against a wall. The spell takes effect immediately on impact. If the spell only affects a single creature (such as shocking grasp), it affects the creature who stepped on it. If it affects an area, the area is centered on the mine. A spell that normally requires a touch attack or ranged touch attack to hit automatically hits a creature who steps on a spellmine, but a ranged touch attack is necessary to hit a creature with a thrown spellmine. A thrown spellmine has a 10ft range increment.
Craft Spellmine [Item Creation]- You can create a spellmine of any 3rd-level or lower spell that you know. Creating a spellmine takes one hour per spell level. When you create a spellmine, you set the caster level, which must be sufficient to cast the spell in question and no higher than your own level. The base price of a spellmine is its spell level × its caster level × 50 gp. To craft a spellmine, you must spend 1/25 of this base price in XP and use up raw materials costing one half this base price. When you create a spellmine, you make any choices that you would normally make when casting the spell. Any spellmine that stores a spell with a costly material component or an XP cost also carries a commensurate cost. In addition to the costs derived from the base price, you must expend the material component or pay the XP when creating the spellmine.