Just to give you an idea of what the JD is up against, here is Mandi as she sails the Sea Wyvern into the start of Into the Maw (I haven't updated her in a while, so quite a bit has changed, especially after I used a limited wish several levels ago to simulate a psychic reformation).
Ozymandia 'Mandi' Enoreth (CR 17)
Female gold elf Wizard 5 / Master Specialist (Transmutation) 10 / Archmage 2
LE Medium outsider (native)
Init +7; Senses low-light vision; darkvision 60 feet; Listen -1, Spot -1
Languages Common, Elven, Abyssal, Infernal, Celestial, Draconic, Maztican
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AC 19, touch 15, flat-footed 14
(+5 Dex, +4 armor)
hp 130 (17 HD)
Fort +13, Ref +13, Will +20; +2 racial bonus against Enchantment effects
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Speed 30 ft. (6 squares), Swim 15 ft. (3 squares)
Space 5 ft.; Reach 5 ft.
Base Atk +8; Grp +7
Combat Gear staff of evocation (31 charges), wand of detect secret doors (48 charges), wand of comprehend languages (50 charges), wand of detect magic (50 charges), wand of knock (50 charges, 11 potions of cure light wounds, 10 potions of invisibility, 10 potions of cure serious wounds, 3 potions of fly, 2 scrolls of Mordenkainen's lucubration, 2 scrolls of Rary's arcane conversion, 5 scrolls of sending, 2 scrolls of teleport, rod of extend spell (lesser), rod of extend spell (greater), rod of empower spell (lesser)
Wizard Spells Prepared (equivalent CL 19th, 22nd for Transmutation, 21st for spells from the Teleportation subschool), +2 to all caster level checks to break SR, can take 10 on all caster level checks, +1 to DCs and SR checks vs. chaotic outsiders, use of circlet of mages (3 charges per day):
9th - Bigby's crushing hand (+46 grapple check), mass hold monster (DC 31), shapechange
8th - mind blank, Otto's irresistible dance, avascular mass (DC 31), prismatic wall (DC 29)
7th - forcecage, glass strike (DC 30), greater arcane sight, final rebuke (DC 29), submerge ship
6th - greater anticipate teleportation, disintegrate (x4) (DC 29), control water
5th - baleful polymorph (x2) (DC 28), cone of cold (DC 26), hold monster (x2) (DC 27), Rary's telepathic bond, plus 5th level Pearl of Power
4th - celerity (x3), dimensional anchor, locate creature, polymorph, solid fog, plus 4th level Pearl of Power
3rd - detect ship, dimension step (x2), fly, greater mage armor, haste, slow (x2) (DC 26), plus 3rd level Pearl of Power
2nd - alter self, glitterdust (DC 23), heroics, scorching ray (+13 ranged touch, 3 rays) (generally empowered by rod of empower spell), see invisibility, snake's swiftness (x2), stormrunner's ward, plus 2nd level Pearl of Power (usually to retrieve scorching ray)
1st - benign transposition, magic missile, nerveskitter, ray of clumsiness (+13 ranged touch, 1d6+5 dex penalty and empowered by spellshard) (x2), shield (x2), wave's blessing, plus 1st level Pearl of Power (usually to retrieve ray of clumsiness)
Cantrips - amanuensis, mage hand, message (x3)
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Abilities Str 8, Dex 20, Con 20, Int 32, Wis 14, Cha 8
SQ Immunity to sleep effects, able to notice secret or concealed doors, prohibited from using spells from the schools necromancy and illusion, no familiar, immediate magic option (PHB II) sudden shift 11/day, minor school esoterica (transmutation), moderate school esoterica (transmutation), major school esoterica (transmutation) 3/day, caster level increase +2 (transmutation), outsider traits, High Arcana (+1 spell power), High Arcana (Arcane Reach), Spell Versatility variant (UA, treat avascular mass as a transmutation spell)
Feats Alacritous Cogitation, Arcane Mastery, Collegiate Wizard, Favored Magic Foe (chaotic outsiders), Greater Spell Focus (Transmutation)(B), Minor Shapeshift, Otherwordly, Scribe Scroll (B), Skill Focus (Spellcraft)(B), Ship's Mage, Spell Focus (Transmutation), Spell Focus (Enchantment)
Flaw Innattentive
Trait Absent-Minded
Team Feats Spell Barrage
Skills Concentration +30, Diplomacy +1, Knowledge (arcana) +34, Knowledge (dungeoneering) +32, Knowledge (nature) +32, Knowledge (the planes) +32, Knowledge (geography) +32, Knowledge (religion) +13, Knowledge (history) +13, Profession (sailor) +27, Search +13, Spellcraft +36, Survival +4
Possessions combat gear plus Ring of Enduring Arcana, Ring of Arcane Might, Tunic of Steady Spellcasting augmented with +4 resistance bonus to saves and +6 enhancement bonus to Con, Third Eye (Penetrate) augmented with +6 enhancement bonus to Int, Bracers of Arcane Freedom, Boots of Big Stepping augmented with +6 enhancement bonus to Dex, Robe of Arcane Might (Transmutation), Belt of Battle, Mage's Circlet, Heward's Handy Haversack, Greater Crystal of Aquatic Action (continually attached to robe), Captain's Cloak (grants +5 competence bonus to Profession - sailor), Gauntlets of Ghost-Fighting, Empowered Spellshard (Ray of Clumsiness), Pearl of Power (2nd level), Pearl of Power (3rd level), Pearl of Power (4th level), Pearl of Power (5th) level, focus for greater anticipate teleportation, focus for submerge ship, focus for shapechange, focus for greater plane shift (Prime Material and the Abyss), 9000 gp ruby dust (for forcecage)
Spellbook spells prepared, plus 0 - all (minus illusion and necromancy); 1st - comprehend languages, expeditious retreat, feather fall, grease, identify, lesser orb of acid, lesser orb of cold, lesser orb of fire, lesser orb of sound, mage armor, mount, true strike; 2nd - bear's endurance, cat's grace, fox's cunning, knock, rope trick, resist energy, wraithstrike; 3rd - dispel magic, fireball, sound lance, water breathing; 4th - assay spell resistance, blast of flame, dimension door, evard's black tentacles, flame whips, orb of force, Rary's mnemomic enhancer; 5th - cone of cold, greater blink, Mordenkainen's private sanctum, sending, telekinesis, wall of force; 6th - antimagic field, Rary's arcane conversion, true seeing, wall of iron; 7th - greater arcane sight, limited wish, vision; 8th - chain dispel, ghostform, maddening whispers, greater plane shift, polymorph any object
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Hook "There are two types of people who cross my path. The first either assist me or get out of my way. The second end up as piles of dust on the floor. Which category shall I place you in?"