From Compendium of Worldly Lore
Gutter Mages are rogues who really badly want to be a wizard but do so in the most rogue way possible, by stealing spell books learning how to master magic items, improvising spells, and stealing them when none of the prior strategies don't exactly pan out.
Role: Spell Utility DPS
Characteristics: Arcane roguelike, who steals spellbooks and masters using magi items
Source: Book of Roguish Lucks
Game Rule Information
The Gutter Mage has the following game statistics.
Abilities: Dexterity is crucial for moving stealthily, Charisma helps gather information, bribe officials, and talk their way out of trouble, Intelligence for skill points and casting
Alignment: Any
Hit Die: d4
Starting Gold: 5d4 x 10
Class Skills
The Gutter Mage's class skills are Alchemy(Int), Bluff (Cha), Climb (Str), Concentration (Con), Craft (Int), Decipher Script (Int), Diplomacy (Cha), Disable Device (Dex), Disguise (Cha), Forgery (Int), Gather Information (Cha), Hide (Dex), Jump (Dex), Knowledge (any)(Int), Listen (Wis), Move Silently (Dex), Open Lock (Dex), Pickpocket (Dex), Profession (any)(Wis), Search (Int), Spellcraft (Int), Spot (Wis), and Use Magic Device (Cha)
Skill Points at 1st Level: (4 + Int modifier) × 4
Skill Points at Each Additional Level: 4 + Int modifier
Class Features
All of the following are class features of the Gutter Mage.
Weapon and Armor Proficiency: A Gutter Mage is proficient with All simple and light martial weapons and all light armor
Spells: Beginning at first level, a gutter mage can cast a small number of arcane spells. To cast a spell a gutter mage must have an Intelligence of 10 + the spell's level, so a gutter mage with an Intelligence of 9 or lower cannot even cast cantrips. These spells are cast as if the gutter mage were a standard arcane caster, with a save DC of 10+ Caster Level.
Gutter mages do require spellbooks though these books rarely resemble those used by wizards. Instead, a gutter mage's spellbook is a collection of pages torn out of other books, scrawled notes, scroll pages that never seem to fade when read, and other bits of magical flotsam. If a gutter mage ever loses his spellbook, he can create another one from found objects and purchased scrolls and scraps. This task takes constant searching and focused effort for one week per class level and costs 500 gp per class level.
If a gutter mage steals a spellbook containing any spells of the highest level, he cast he need not create another one/ Instead he "adopts" the new spellbook as his own. In time he can add to it normally; he cannot use spells in the book that are not on the gutter mage spell list, except by scribing them onto scrolls.
A gutter mage can make a stolen spellbook his own through one week's study and a successful Spellcraft check (DC15+ the highest level of spell in the spellbook). If the check fails, the gutter mage must spend another week in study before trying again.
Scribe Scroll: A gutter mage can read arcane spell scrolls and gains scribe scroll as a bonus feat. This benefit includes the to read scrolls of arcane spells not on the gutter mage spell list.
Sneak Attack: If a gutter mage can catch an opponent when he is unable to defend himself effectively from her attack, she can strike a vital spot for extra damage.
The gutter mage’s attack deals extra damage any time her target would be denied a Dexterity bonus to AC (whether the target actually has a Dexterity bonus or not), or when the gutter mage flanks her target. This extra damage is 1d6 at 1st level, and it increases by 1d6 every two gutter mage levels thereafter. Should the gutter mage score a critical hit with a sneak attack, this extra damage is not multiplied.
Ranged attacks can count as sneak attacks only if the target is within 30 feet.
With a sap (blackjack) or an unarmed strike, a gutter mage can make a sneak attack that deals nonlethal damage instead of lethal damage. She cannot use a weapon that deals lethal damage to deal nonlethal damage in a sneak attack, not even with the usual -4 penalty.
A gutter mage can sneak attack only living creatures with discernible anatomies—undead, constructs, oozes, plants, and incorporeal creatures lack vital areas to attack. Any creature that is immune to critical hits is not vulnerable to sneak attacks. The gutter mage must be able to see the target well enough to pick out a vital spot and must be able to reach such a spot. A gutter mage cannot sneak attack while striking a creature with concealment or striking the limbs of a creature whose vitals are beyond reach.
Ward Sight Su: When a gutter mage reaches 4th level, he gains the supernatural ability to recognize warding spells, runes, and magic traps, icluding spells such as glyph of wardinf, sepia snake sigil, alarm and so forth. He may use this ability as a full-round action a number of times per day equal to 3 + his Intelligence modifier. Ward sight acts as a rogues class' trap sense ability but requires a single successful Search check to see all the wards and magic traps on an object. A Disable Device check is needed to deactivate any magic traps found. When a gutter mage uses ward sight and finds active wards, he sees wards without further need for concentration until they are removed. As long as he can see such wards, a gutter mage can attempt to disarm them as if they were physical traps. For a gutter mage, a spell's default Disable Device DC is 15 + spell level.
Nondescript Ex: At 5th level or higher a gutter mage can pass without notice in a crowd or an area filled with other creatures and can effectively hide in a crowd as if hiding in the shadows. Indeed, a gutter mage is often entirely overlooked by guards and searchers when at least 10 other creatures are present. Using this ability in plain sight requires a successful Disguise check opposed by the watcher's Spot check.
Even if the Spot check succeeds, watchers see the gutter mage but don't regard him as worth noticing - they are not immediately suspicious. Normally, a failed Disguise check makes other suspicious of the disguised person's activities or appearance. With the nondescript ability, only particular offensive actions, such as combat, thievery, or spellcasting are likely to trigger suspicion in the watchers.
Improvise Spell Sp: At 8th level or higher, a gutter mage can attempt to cast a higher-level arcane spell that he doesn't really understand, albeit with a higher than usual risk of backfiring. He cannot improvise a spell of a level higher than the highest-level spell he can cast.
Improvising a spell is a form of spontaneous casting that uses up existing spell slots similar to a cleric's or druid's ability. An improvised spell normally takes up a spell slot equal to the level of spell being cast, but if the gutter mage has no slots available (if he has already expended all spell slots of the appropriate level for the day), he can expend two spell slots of the next lower level instead. The spells in those slots are lost. If those slots are already expended as well, the character cannot use this ability.