From Compendium of Worldly Lore
Elves have an affinity to magic and its study, and it shows in the way many of them have at least rudimentary knowledge of wizardry while pursuing other careers. However, some push their powers even further, going beyond the capabilities of normal wizards into a finer and more precise control of the magical energies that make spells work. The arcane delvers are not organized, but receive their due recognition by their peers in elven magical schools. A young elf apprentice studying under an arcane delver has the option to learn his master’s secrets once he proves he is worthy of them, or he may continue to study the arcane arts normally. Beyond the walls of magical academies, arcane delvers are no different than other wizards, and people think of them only as particularly talented spellcasters.
Arcane delvers are mainly wizards, as sorcerers rarely come upon an arcane delver willing to train them into his secrets, unless they risk the scorn of the learned spellcasters and enter an academy. Bards face the same problem, but they are less interested in honing their spellcasting skills than sorcerers may be. There is no record of divine delvers, but it is not unthinkable that a cleric following a deity of magic could learn some of the arcane delver’s tricks. The meticulous academies of the grey elves produce more arcane delvers than the more informal wizard masters of the high elves, and they are unheard of among the wood and wild elves. Sea elves become arcane delvers with the same frequency as high elves, and drow males gain a measure of respect when joining their ranks.
Arcane delvers fill the role of the elusive sage who knows all there is to know about the magic art, and it is rare to find them on the road except on ‘practice’ trips, where they test their control of their powers.
Role: Spell
Characteristics: Experts of placing their spells in objects and timing them
Source: Quintessential Elf
Game Rule Information
The Arcane Delver has the following game statistics.
Abilities: Whatever your casting stat is and Cpnstitution as concentration is key here for this class
Alignment: Any
Hit Die: d4
Starting Gold: N/A
Class Skills
The Arcane Delver's class skills are Alchemy (Int), Concentration (Con), Craft (Int), Knowledge (all skills, taken individually) (Int), Listen (Wis), Profession (Wis), Scry (Int, exclusive skill), Search (Int), Spellcraft (Int), and Spot (Wis).
Skill Points at 1st Level: (2 + Int modifier) × 4
Skill Points at Each Additional Level: 2 + Int modifier
Class Features
All of the following are class features of the Arcane Delver.
Weapon and Armor Proficiency: A Arcane Delver is proficient with dagger, quarterstaff and crossbow. They are not proficient with any kind of armor nor with shields
Spells: At every odd level, the arcane delver gains additional spell slots as if he had gained a level in the spellcasting class he belonged to before adding the prestige class. However, he does not gain any other benefit a character of that class would have gained with level advancement (hit points, feats, special abilities, character had more than one spellcasting class before becoming a speaker, he must decide to which class he adds the new level for purposes of determining spells per day.
Shape Spell Su: The arcane delver has a much finer control of his spells’ energy, and can shape an area of effect in ways undreamt of by other wizards. The character must roll a Spellcraft check (DC 15 + spell level), for every two points that the result exceeds the DC, he can change how the spell affects a single five-foot square or move one such square around the affected area. He can make his spell have no effect on a square inside the normal area, for example. With this ability, a ray might snake around allies to hit an enemy, a fireball might explode but strangely not affect choice places inside it, or a lightning bolt could curve slightly to hit opponents adjacent to, but not inside the line of effect. The wizard still needs line of sight to target a creature, but if he rolls a high enough result in the Spellcraft check, he may not need a straight line of effect.
Time Spell Su: The character can delay the activation of a spell as he casts it. As part of a normal spellcasting action, the arcane delver can choose to delay the spell up to 4 rounds. He decides how many rounds the spell will wait at the moment of casting, and he is free to perform any action in the interim, including casting other spells. He suffers one point of temporary Constitution damage for every round the spell is delayed, as he is keeping the triggered magical energies inside him until they are unleashed. If he suffers any damage before his delayed spell activates, he must succeed at a Concentration check (DC 10 + spell’s level + damage received) or the spell dissipates.
Place Spell Su: The arcane delver can bend the arcane pattern of a spell’s energy and entwine it within an object. The character creates temporary magical items in this way, storing a spell until he or another spellcaster triggers it as if he were casting it. Any person may activate the spell with a simple Concentration check (DC 15) and its activation does not require preparation or spending of a spell slot. The arcane delver spends 5 XP per spell’s level and suffers one point of temporary Intelligence damage per two levels of the spell. The enchanted item shows on detect magic until the spell is released, becoming a mundane object in the process.
Disrupt Spell Su: The character knows how magic is shaped on a raw and basic level and finds it easier to disrupt other spells. The arcane delver does not need to unleash the same spell an opposing caster casts in order to counter it, instead he rolls the normal counterspell Spellcraft check in order to identify the spell’s level, and then sacrifices a spell one or more levels higher to the one he wants to counter. The delver is merely throwing the spell’s raw energy to smother and shatter the target spell.
Intermittent Spell Su: The arcane delver has such control over his magic that he can switch ‘on’ and ‘off’ any spell with a duration longer than instantaneous. After casting the spell and as a partial action, he can roll a Concentration check (DC 15 + spell’s level) to suspend the spell’s effect until the beginning of the next round. Creatures inside the area must roll their saving throws again once the spell reactivates. The character cannot make an intermittent effect for spells with a duration of instantaneous or concentration, and the spell ends after its normal duration, regardless of how many times it was interrupted.