Well lookie there... Red Dragon Advancement, Great Wyrm 41+... There's no advancement cap.. Let's see how insane the most powerful reds can get...
Oh good gracious... I love CRG's Dragon Generator.
GREAT WYRM RED DRAGON
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Colossal Dragon (Fire)
Hit Dice: 1000000039d12+8000000312 (14500000565 hp)
Initiative: +3
Speed: 40 ft, fly 200 ft (clumsy)
AC: 40 (-1 Dex, -8 size, +39 natural)
Attacks: Bite +1000000048 melee, 2 claws +1000000043 melee, 2 wings +1000000043 melee, tail slap +1000000043 melee
Damage: Bite 4d8+17, claw 4d6+8, wing 2d8+8, tail slap 4d6+25
Face/Reach: 40 ft by 80 ft / 15 ft
Special Attacks: Breath weapon, locate object, other spell-like abilities, frightful presence
Special Qualities: Fire subtype, immunities, DR 20/+3, blindsight, keen senses, SR 32
Saves: Fort +500000029, Ref +500000020, Will +500000029
Abilities: Str 45, Dex 9, Con 27, Int 25, Wis 27, Cha 26
Skills: Bluff +1000000047, Concentration +1000000047, Diplomacy +1000000047, Escape Artist +1000000038, Knowledge (arcana, geography, history, religion) +1000000046, Listen +1000000049, Scry +1000000046, Search +1000000046, Sense Motive +1000000047, Spellcraft +1000000046, Spot +1000000049
Feats: Hover, Flyby Attack, Power Attack, Cleave, Snatch, Improved Initiative, Spell Focus (Evocation), Alertness, Wingover, Quicken Spell-Like Ability, Sunder, 249999999 more
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Challenge Rating: 50000024
Alignment: Always chaotic evil
SA–Breath Weapon (Su): Cone of fire, 70 feet long, every 1d4 rounds; damage 24d10, Reflex half DC 500000037.
SA–Frightful Presence (Ex): Dragons can unsettle foes with their mere presence. This ability takes effect automatically (radius 360 ft) whenever the dragon attacks, charges, or flies overhead. A potentially affected creature (one with less than 1000000039 HD) that succeeds at a Will save (DC 500000037) remains immune to that dragon's frightful presence for one day. On a failure, creatures with 4 or fewer HD become panicked for 4d6 rounds and those with more than 5 HD become shaken for 4d6 rounds. Dragons ignore the frightful presence of other dragons.
SA–Locate Object (Sp): This dragon can locate object 12/day as the spell of the same name.
SA–Other Spell-Like Abilities: 3/day - suggestion; 1/day: eyebite and discern location.
SQ–Immunities (Ex): Immune to sleep, paralysis.
SQ–Blindsight (Ex): Dragons can ascertain creatures by nonvisual means (mostly hearing and scent, but also by noticing vibrations and other environmental clues); this dragon's range is 360 feet.
SQ–Keen Senses (Ex): Dragons can see four times as well as humans in low-light conditions and twice as well in normal light. They also have darkvision (range 1200 feet).
SQ–Fire Subtype (Ex): Fire immunity, double damage from cold except on a successful save.
Spells Known (cast 6/8/8/8/8/7/7/7/7/4; as a level 19 sorcerer): 0–detect magic, resistance, detect poison, read magic, dancing lights, ghost sound, mage hand, open/close, mending; 1–endure elements, mage armor, divine favor, cure light wounds, shield; 2–bull's strength, cat's grace, blur, endurance, fog cloud; 3–haste, dispel magic, protection from elements, slow; 4–spell immunity, dimension door, improved invisibility, detect scrying; 5–cloudkill, righteous might, dominate person, teleport; 6–heal, greater dispelling, harm; 7–spell turning, destruction, greater scrying; 8–mass charm, maze, protection from spells; 9–miracle, foresight.
Oh drat, forgot to make it a 20th level character. Um.. Add 20 levels of Bard in there for fun.
(Don't forget to have the dragon use miracle to cast Greater Magic Fang...

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