Note: I have taken some liberty with the CR of this character. Because the skills he acquired as a Paladin for four levels virtually disappear (save some bonuses from being Blackguard) after Falling, I'm not counting the Paladin levels in the CR; you can bump him up a CR level or two if you feel that balances this NPC.
Galen Medici: Paladin (fallen) 4, Sorcerer (Necromancer) 6, Blackguard 3
Hit Dice: 4d10 plus 6d4 plus 3d10 (47 hp)
Armor Class: 19 (+1 ex, +5 Armor, +3 Bracers)
Base Attack/Grapple: +7/+9
Attack: +1 Cold Battleaxe +8 melee (1d8+3 plus 1d6 cold damage)
Full Attack: same
Special Attacks: Smite Good 2/day
Special Qualities: Aura of Despair, Aura of Evil, Command Undead, Dark Blessing, Detect Good, Poison Use, Lay on Hands
Saves: Fort. +11, Ref. +6, Will +9
Abilities: Str 15, Dex 12, Con 11, Int 10, Wis 13, Cha 16
Skills: Diplomacy +9, Heal +11, Hide +6, Intimidate +8, Knowledge: Religion +2, Ride +3, Sense Motive +3
Feats: Cleave, Craft Undead(B), Improved Sunder, Power Attack, Still Spell, Craft Wondrous Item
Challenge Rating: 9
Alignment: Lawful Evil
Galen's relationship with the aberrations and other fell beasts grew and he all but forgot his days as a paladin. His new goal in life was to rescue as many people as possible from the grips of disease and death. To him, this involved two things. First, the greatest threat Galen found was the rampant spread of disease amongst the humans. Animals and beasts were able to keep epidemics rare and few between, but humans fell sick quite often. Therefore, his first order of business would be to kill those too weak to defend themselves against him, since surely they would not be strong enough to withstand an epidemic and would just become plague carriers, so better to destroy them now.
Second, he was the only one who was seeing clearly on this issue, so he had to ensure his longetivity in order to continue his 'good' works. So he learned how to create his own Phylactery with the intent that it would restore his life if he were to die (he was lied to by the fiends who taught him to make it, about what a lich actually is). He therefore created a Phylactery with the help of a more powerful sorcerer, and waited.
Wealth level is 40,000 gold, so equipment is a Flaming +1 Battleaxe (12 + 300 masterwork + 8000 enchantment = 8,312 gp, 5 lbs.), Bracers of Armor +3 (9,000 gp), a suit of +1 Mithril Scale Mail (50 + 4,000 mithril + 1,000 enchantment = 5,050 gp; Light armor, AC +5, Max Dex +5, Check Penalty -1, Spell failure 15%, 15 lbs), a Minor Ring of Fire Resistance (fire resist 10, 12,000 g), a Wand of CLW (375 gp, 50 charges), and five doses of Medium spider venom (Injury DC 14, 1d4 Str/1d4 Str; 150 g each, 750 g total) for a total of 35,487 gold worth of equipment, leaving 4,513 remaining for his horde.
Custom Feat: Craft Undead: This feat allows the character to craft a zombie like the spell Animate Dead but using a process that's more like a golem construction (lesser flesh golem); it's using healing and science to bring life back to dead tissue, rather than magic. To create zombie, the appropriate body that's laid out in the Animate Dead spell description must be obtained, and prepared using 100 gp worth of healing oils, herbs and equipment. Assembling the body requries a DC 11 Heal check. The construction of a zombie requires 3 hours and takes no XP loss
Phylactery: Galen has made a Phylactery for himself in preparation for becoming immortal. It is hidden on the Ring of Fire Resistance (there are three gems in the ring; one is the phylactery, the other two give fire resistance). As a phylactery, the ring has 40 HP, hardness 20, and a break DC of 40.
Aura of Despair (Su): Beginning at third level, a blackguard radiates a malign aura that causes enemies within 10' to take a -2 on all saving throws.
Aura of Evil (Ex): The power of a Blackguard's aura of evil is equal to their class level plus their cleric level, if any.
Command Undead (Su): When a blackguard reaches third level, they gain the ability to command and rebuke undead. They command as a cleric of two levels lower (1st).
Dark Blessing (Su): The blackguard applies his Chr mod (if positive) as a bonus to all saving throws.
Detect Good (Sp): At will, a blackguard can use detect good as a spell-like ability, duplicating the effect of a the detect good spell.
Lay on Hands (Su): A blackguard with a Chr. score of 12 or more can heal wounds (themselves or others) by touch. Each day, a blackguard can heal a number of hit points equal to their blackguard level x their Chr bonus (3x3 = 9). This healing can be spread out over multiple targets (all touched), or used to deal equal damage to a touched undead (no AoO given to the undead touched).
Poison Use: Blackguards are skilled in the use of poison and never risk accidentally poisoning themselves when applying poison to a blade.
Smite good (Ex): Once per day, a blackguard may attempt to smite good with one normal melee attack. They add their Chr mod (if positive) to their attack roll (+3) and deals one extra point of damage per class level (+3). If a blackguard accidentally smites a creature that is not good, the smite has no effect, but is used up for the day.
Spells (Blackguard): Two first level spells per day, DC is 11 plus spell level. 1st - Inflict Light Wounds, Magic Weapon
Spells (Sorcerer): 6/7/5, DC is 12 plus spell level. Necromancer (Div and Trans banned; starred spells bonus Necro spells). 6/4/2 spells known: 0th - *Disrupt Undead (Necro; V, S), Resistance (Abjur; V, S, M), Acid Splash (Conj; V, S), Ghost Sound (Illus; V, S, M), Touch of Fatigue (Necro; V, S, M), Flare (Evoc; V), Ray of Frost (Evoc; V, S), 1st - *Ray of Enfeeblement (Necro; V, S), Cause Fear (Necro; V, S), Magic Missile (Evoc; V, S), Burning Hands (Evoc; V, S), Shocking Grasp (Evoc; V, S), 2nd - *Command Undead (Necro; V, S, M), False Life (Necro; V, S, M), Darkness (Evoc; V, M)