How challenging is Typhon?

[Gilda]

Hi everyone, I have a mechanical question for my 3.5 Greek mythology campaign. I have a party of the following:
Cleric w/ Paladin cohort
Bard w/ Wizard cohort
Barbarian whose cohort is a Blink Dog taking martial class levels
To be assisted by their friend Cadmus (whirling frenzy lion totem Barb 1/Fighter X/Cleric 8)

... and I've been setting up Typhon to be the final boss since they first angered Gaia by killing a priest of hers (he was trying to kill the Cleric of Apollo for being the one to rededicate Delphi to him after Apollo slew her pet dragon who liked to abduct Oracles).
When Typhon eventually attacks, the 12 Olympians minus Zeus will hide in Egypt, leaving behind 3 +5 piercing weapons that always get 20 on attack rolls (see Deities & Demigods) and Apollo's Lyre of Charm Monster No Save. Their armor will have been enchanted with fire immunity.
Here's how I have him stated up:

Typhon is treated as 102 colossal and 8 gargantuan creatures connected to the same torso. All have Divine Rank 19/divine immunities + fire - electricity & mind-affecting effects/AC 97/DR 45(+4)/SR 42/STR 48, DEX 10, CON 34, WIS 26, CHA 28/Saves: Fort +57, Ref +45, Will +52.
2 legs: colossal dragons. Speed (moves all parts) 40 ft, swim 40 ft. INT 2. Except as noted, treat these parts as Tiamat with 5 green heads & without spells or spell-like abilities.
100 arms: colossal dragons. 740 hp (40d12+480). Full attack: +70/+65/+55/+50 bite for 4d8+19 & 2x +65 claw for 4d6+9. Breath is 24d10 fire damage (DC 56 Ref for half). Speed 65 ft (ie swinging a 65-foot-long arm), swim 65 ft. INT 2. Caster level 1st.
8 heads: gargantuan aberrations. 561 hp (34d8+408). Speed 0 ft. Special quality: a medium or smaller creature standing on Typhon can Climb or Jump into an ear (DC 52). When in an ear, only one of Typhon's arms can attack the creature, who on an attack roll of 20 with a piercing weapon hits the brain. Brain death occurs if a brain takes 148 damage.
Heads of a man & a lion fight as Beholders. Heads of a wolf & a dog fight as 19th level Sorcerers. Heads of a bear, boar, bull & leopard fight as 19th level Clerics.

If I have Zeus tell them the heads's weak point, at what level can I expect trying to kill them to weaken Typhon to shift from a TPK to a challenging boss fight? From challenging to anticlimactic? The material we're using is just SRD/Core + Deities & Demigods, the Barbarian is played by a powergamer, the Bard & Wizard have an experienced player, the Cleric & Paladin are played by a first-timer.

[Remuko]

That sounds amazing and I'm sorry I don't have too much insight but I have to ask, if you are using Deities and Demigods rules shouldnt each "part" of Typhon have max hp based on his divine rank? If so I think the HP values are a bit off in your post. The dragons should have 960 HP and the heads should have 752 HP.

[gawwy]

Ive looked a few times at your post but im still missing what level your pcs are at. help a brother out? also when they are in the ear canal can the one arm that can attack them physically hit them or can it only breath weapon?

[Gilda]

Ive looked a few times at your post but im still missing what level your pcs are at. help a brother out? also when they are in the ear canal can the one arm that can attack them physically hit them or can it only breath weapon?

They can be physically hit from the one tile behind them, as the creature's front and sides are shielded by the earlobe.
Right now, they're only Level 11. They figured out Typhon exists 16 IC months ago at Level 7, after they killed the highest-level Gaia priest (Druid) in the Greek peninsula and his henchmen suddenly vanished "to celebrate a wedding." The PCs are terrified of what they know, and they're having sandbox adventures while Typhon is being held back until Orthrus, Cerberus, the Lernaean Hydra and Chimera are all born.
The question is, how high should I let the party level before releasing Typhon? Like at 17, the Cleric can Resurrect or Raise Dead 8 times a day, allowing his friends to make several suicide runs on the heads and expect to be alive again the next day, and two more levels gives the Wizard cohort her first Wish.

Remuko: Oh, good catch. I was looking at Tiamat there, and she doesn't seem to have full HD 49d12+588 = 906).

[Remuko]

Remuko: Oh, good catch. I was looking at Tiamat there, and she doesn't seem to have full HD 49d12+588 = 906).

I think only DR15+ have max hp per HD tiamat is only DR 10 iirc

[Harlekin]

Hi,

first, I think you either calculated the Spell Resistance and Damage Reduction wrong or the divine rank 19 is atypo and should be 10. Deities and Demigods says on pg. 26/27 Deities have SR 32 plus divine rank and DR 35 plus divine rank/+4. With a divine rank of 19 it should be SR 51 and DR 54/+4 instead of SR 42 and DR 45/+4.

I'm not too familiar with high level optimization, but a SR of 51 seems quite unbeatable in core only, even at level 20 (with the exception of a group of red wizards), and the SR 42 is still hard to beat. Everything which allows a save is out. Again if the divine rank is 19 the "always maximize roll" ability makes the saves Fort: 77 Ref: 65 Will: 72, and I think there is no way to get your save DC that high in core only. If the divine rank is 10, there is still the "deities don't fail on a natural 1" clause, which makes the saves at least Fort: 58 Ref: 46 Will: 53 on a roll of 1.

In addition there is the ability to cast all domain spells it can grant as a spell-like-ability at will, the almost unlimited xp-reserve for casting and crafting, the salient divine abilities, the different immunities, teleport without error and plane shift at will and (if divine rank 19) the ability to change gravity, energy, elemental and time traits of its realm at will.

In addition, there are two beholders, two 19th-level sorcerors and four 19th-level clerics.

I don't see any exploitable weaknesses here, except perception, which should be covered with the clerics, sorcerers, salient divine abilities or free item crafting.

I think, if Typhon is played smart, there is now way your party can win this. The ear thing looks like it's supposed to be the solution, but if i were Typhon, i'd have a contingent teleport if someone gets into my ear...

[ZamielVanWeber]

I should point out that Deities and Demigods was updated to 3.5. This includes their DR being reduced to a lower number and becoming /epic, which +5 weapons are not able to penetrate.

Also I am not sure how your players are supposed to win reasonably. Divine Rank 19 comes with some powerful benefits that require planning and optimization to counter, especially since you have such an insane number of enemies. The real question once Divine Rank 1+ comes into play is how well have the players optimized for power?