Help with an Iconic Encounter (Members of the Crystal Order stay out, please!)

[Lappy9001]

Members of the Crystal Order, please refrain from reading this thread. Spoilers from the campaign are below.
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Okay, so I need some help in making a section of my campaign suitably epic for the players. Namely, they're going to eventually encounter an Ancient Red Dragon. Not just any ancient red dragon, but (due to the nature of the world) the most powerful red dragon and possibly the most powerful dragon in the world who houses an imprisoned god beneath her lair as the crowning treasure of her hoard.

I have plans for the encounter (not that they actually have to fight and/or kill her) and the raid on her lair (the players will need to contact the god for information) to take up a good chunk of the next section of the campaign. I feel that this should be a BIG deal but I've never actually run a dragon this powerful in a game before. The system is Pathfinder and the campaign is the one in my signature if anyone wants more information.

TL;DR Does anyone have any tips on experiences making encounters with an ancient and powerful dragon and the raid on their lair truly epic and memorable?

[Strigon]

Well, what is the dragon's power level compared to the party's?
Can she crush them without a second thought, will the party win if they get lucky, or is it a fair fight?
Because making epic encounters for each of those three scenarios are entirely unique beasts.

[Lappy9001]

Well, what is the dragon's power level compared to the party's?
Can she crush them without a second thought, will the party win if they get lucky, or is it a fair fight?
Because making epic encounters for each of those three scenarios are entirely unique beasts.

They will be about level 12 or so by the time this comes about. I'm considering modifying an Adult Red Dragon so that the challenge rating will be closer, but the more I thought about it, the more I think I want a toe-to-toe fight to be unnecessary. I do plan to have a ton of dragon-themed minions about to give the PC's some combat, though.

[Dire Moose]

First off, make it clear to them that the dragon is way beyond their power level to the point where they couldn't possibly win in a traditional fight. A TPK is never a good thing.

Second, if you haven't done so recently, you should definitely read the relevant portions of The Hobbit for ideas on how to play out such an encounter.

[TurboGhast]

If the PCs can't win in a straight fight, add things to the environs that allow odd tactics that could help them get an edge. Don't make the advantageous tactics to obvious or preplanned, however.

[Strigon]

Well, presumably you'll then want a lot of things other than the dragon to interact with.
Lots of traps, and lots of minions. The issue becomes having areas large enough for the dragon to pass through that can also be effectively trapped. Figure out a way to do that, and your job just became much easier.

Also, nearly all of the most epic encounters have one thing in common, and that is suitable epic terrain. Make sure it's:

• Varied
• Interesting
• Cohesive
• Littered with things you can interact with

Keeping things varied and cohesive can be difficult, but all I can say is try to make each area you expect to be important have at least one interesting thing. A trap, a balcony, cover, rough ground, hazards, that sort of thing. This isn't to say every square has to have something on it, but if you divide the room/corridor/whatever into sections, each section should have something interesting going on.
Then make them all come together thematically; find a reason why each "thing" should be in that room.

[DigoDragon]

Due to the action economy favoring the party, the way I ran dragon boss battles is to give the dragons several minions as support. They flank, they buff, they hinder PC movement on the battlefield. The minions aren't too difficult to deal with, but if the players ignore them to attack the dragon directly, they make the fight that much more difficult for themselves.

[Lappy9001]

Thanks for the responses so far! I guess I should also ask if I should use the CR 19 dragon or a CR 14 dragon (with maybe the Advanced template) for a party of five 12th level adventurers? Is it a better idea to make the encounter a straight up cinematic fight or create a scenario where the PC's are clearly outclassed and need to find an alternate way to get what they need? Either way, there hasn't been much along the lines of a dungeon crawl, so the change of pace will be welcomed.

For some background, the party consists of a Gnome Summoner, a Human Vitalist (Dreamscarred Press), a Dwarf Fighter, a Tiefling Rogue, and a Vampire Harbinger (Also DSP). They have shown that they're more than capable of walking away from challenges far above their CR but they're also smart; they know a hint of "this thing is way more powerful than you" when they see it.

In the setting, most dragon eggs turn into mutants such as kobolds, drakes, and dragonspawn with true dragon births being exceptionally rare. There should be no shortage of draconic minions and while most will be reds, I'm thinking of adding another type like blues or whites.
Maybe the main dragon is being courted by a white/blue dragon who is an acceptable, if not preferred suitor and has produced some different elemental babies (the vampire will appreciate it for sure, since he's stuck with fire vulnerability that he can't get rid of).

[Lvl 2 Expert]

From the opening post I'm imagining a bit of a "mouse world", with the party hiding in small tunnels connecting the various larger rooms and hallways of the lair and being chased by minions etc while trying to avoid this enormous dragon, way bigger and more powerful than anything the players have ever gone up against.

That might not be the best option though, as you said, it's probably fun if they can eventually defeat it. You need to find a way to keep the characters from doing so (or dying in an attempt) before they have have spend some time sneaking around, exploring the lair and talking to the god. Minions ans traps are probably a good way to do that. The players need to find a way to cut off the reinforcements so that they can fight the dragon alone. And even then they might need a special hint about where to aim or a magical weapon or something.

Whichever way you go, it's probably cool to have at least one conversation scene with the dragon, where she tells them some stuff about how they'll never beat her and her army of whatevers, how even a god couldn't stand up to her, some hints at where to look like that.

[goto124]

Whichever way you go, it's probably cool to have at least one conversation scene with the dragon, where she tells them some stuff about how they'll never beat her and her army of whatevers, how even a god couldn't stand up to her, some hints at where to look like that.

If she's actually powerful, why would she feel the need to show off so much?