[Epic Level] Zeitgeist vs. Colossus

[Mr.Kraken]

So, I'm DMing a campaign that's heading into epic level and I want to prepare for one of the key events of ths story. There's a war brewing between the two main city-states of the world - let's just call them the good city and the bad city. So, there've been rumors that the bad city is developing a new secret weapon to be used against the good city that the players defend. They will, in a couple of sessions, find out that their secret weapon is, in fact, FOUR Iron Colossus (Colossi?). When the war eventually starts, the bad city will set the constructs against the good city and chaos will ensue (feeding the antagonist of the campaign - Tharizdun himself).

The idea is that when the colossus and the rest of the bad city army march against the good city, the players will be told that they have a secret weapon of their own - the city itself! A Zeitgeist (CityScape) will, then, materialize and defend the city against the constructs.

I'm planning on having the players disable one of the colossus before they finish its construction, so the bad city will march alongside three iron colossus, while the good city will have the zeitgeist to defend itself. And here we have the problem. It's not a fair fight at all!

I have little experience with D&D (I've been a GURPS DM for most of my life), but I've learned the ropes and now have some passable experience. But, I've never DM'd an Epic Level Campaign. I liked the idea of the Zeitgeist as a creature that reflects the city itself and wanted to have an titanic battle using it and the colossus - the bad city is more mechanical and warlike.

The thing is the Zeitgeist has very bad stats compared to the Iron Colossus, so I've been planning on using the Stone Colossus (refluffed) instead and advancing the Zeitgeist. But still, there're a lot of problems. I want the zeitgeist and the 3 colossi to destroy each other - so, one Zeitgeist has to be comparable to three stone colossus, which to me, seems impossible. The Zeitgeist causes too little damage and relies on magic. The colossus has monstrously high attack bonus, damage, AC, damage resistance and fricking immunity to magic.

Can you guys help me? What should I do in this situation? How can I advance the zeitgeist to fill in that role?

[Extra Anchovies]

Hm. Three stone colossi = nominal CR of 27. +4 CR to a fey is +16 HD, so a CR 27 Zeitgeist should have 36 HD (and thus be of Gargantuan size). To compensate for fact that the Zeitgeist seems a little over-CR'ed, give it the elite array. Then add two more Zeitgeists.

No, really, make there be three of them, all at 36 HD. One in Smoke form, one in Mob form, and one in Stone form. Evens the action economy, and compensates for the fact that you have a trio of magic-immune bruisers up against a creature whose main assets are its SLAs.

[PraxisVetli]

Forewarning.
Fair amount of houseruling ahead.
I recently had my players against a Zeit, but I modded its forms.
Mob was a gang of ghastly (dragon comp) evolved (lib mort) spellstitched (mm..3?) chokers.
Smoke was an advanced Alkilith (fiend folio) symbiote Belker (mm)
Construct, I just advanced, paragon, devil posessed (dragon comp). Admittedly, the devil possesed was storyline, but meh.
And if this is not helpful, sorry..
Epic level, you gotta bend some rules.

[XionUnborn01]

Okay, given the CR differences, have you thought about using the stats for a Primal Air Elemental in place of the Zeitgeist? It evens up the playing field a lot, especially because you could due a primal air, stone, and fire elemental and it still fits in the Zeitgeist theme because their smoke form is fire and air type and the image of huge chunks of the stone roads and ground combining into a giant elemental that could obviously represent the stone form.

The colossus is CR 33, the elementals are CR 35 so if you do 3 on 3, you should have a pretty even match CR wise, but I have no idea how the elementals would fair against the colossus because I didn't take the time to compare stats.

I think that would really make your life easier and require significantly less prep work.

[ben-zayb]

There's a slight problem with your plan: Zeitgeists are incorporeal!

Unfortunately, Rules Compendium has this, IMO, silly clarification that any incorporeal creature winks out in an AMF. SRD (http://www.d20srd.org/srd/specialAbilities.htm#antimagic) seems to have adapted that stance.
Summoned or conjured creatures of any type, as well as incorporeal creatures, wink out if they enter the area of an antimagic effect. They reappear in the same spot once the field goes away.

IF you ignore that rule, that means that the Colossi will do jack**** against the almighty Zeitgeist. Due to the suppression of the Zeitgeist's bread and butter SLAs, it will have to rely on its Extraordinary attacks. Smoke Form's Choke won't work on constructs, while Fiery Slam will likely be absorbed by DR if it counts as weapon attack. Human Mob Form's 5d6 bludgeoning damage from mob Attack is reduced (and on average, cancelled) by DR, while Trample seems to work. But all of that is assuming that the two will be able interact despite the Zeitgeist's incorporeality.

EDIT: Oops, thought it was stone colossi. Iron Colossi can use Breath Weapon against the Zeitgeist.

[Mr.Kraken]

There's a slight problem with your plan: Zeitgeists are incorporeal!

Unfortunately, Rules Compendium has this, IMO, silly clarification that any incorporeal creature winks out in an AMF. SRD (http://www.d20srd.org/srd/specialAbilities.htm#antimagic) seems to have adapted that stance.

IF you ignore that rule, that means that the Colossi will do jack**** against the almighty Zeitgeist. Due to the suppression of the Zeitgeist's bread and butter SLAs, it will have to rely on its Extraordinary attacks. Smoke Form's Choke won't work on constructs, while Fiery Slam will likely be absorbed by DR if it counts as weapon attack. Human Mob Form's 5d6 bludgeoning damage from mob Attack is reduced (and on average, cancelled) by DR, while Trample seems to work. But all of that is assuming that the two will be able interact despite the Zeitgeist's incorporeality.

EDIT: Oops, thought it was stone colossi. Iron Colossi can use Breath Weapon against the Zeitgeist.

Forgot to mention. The plan is to have the players disable the colossi's antimagic field - which, in storyline, is given by a special magic item that they will have to destroy. So, it will be a fist-on-fist godzilla-like battle, and the players will fight alongside the Zeitgeist.

Another problem with my plan is that I completely ignored the Zeit's size. He can be advanced only to gargantuan, and I've planned on having him Colossal instead. I did what Extra Anchovies recommended and bulked him up to 36 HD and increased his size to colossal instead of gargantuan. I also made the zeitgeist able to manifest into his three forms at the same time, so he'll face all three colossi at once. That made the fight a little bit more even. I'll have to figure a way to give him adamantine strikes to bypass the colossi's DR, though... or not.

[Mr Adventurer]

Have the city animate as a Genius Loci instead! Or as well!

http://www.d20srd.org/srd/epic/monsters/geniusLoci.htm