Fun with counterfactuals
This is written as an address to the players, as it is a straight lift from the FB group posting
What if...the party hadn't used Diplomacy in the initial encounter?
The warring Daeva factions would have united against the "outsiders". You'd have beaten them, for sure, but you wouldn't have gained a more or less immediate lead on where Sunaeco was.
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What if...the party somehow screwed up and killed Godratt?
There was a tense moment when this almost looked like it might happen. Anyone who had actually read the Janni Vizier's tale at the start of the adventure properly and digested it should have been able to guess who the guy on the floor was, but when he auto-resurrected the party were still in a mode of seeing everything but Sunaeco as a threat. For a second there it looked like you might quickly try to kill him "before he gets a spell off" (actually, funnily enough that's exactly what the Rakshasa boss [in his Devourer meat suit] did).
Needless to say, that would mean the Mirror couldn't be destroyed. At least, not within the scope of this adventure.
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What if...someone had checked out the Sepulchre of Delir the Brave before going down the shaft beneath the Sepulchre of Ghalandar and freeing Sunaeco, or else a bit later when searching for the diamond?
For a moment, Baurig almost stepped into that place. He looked in and saw a couple of Aesma Daevas. Then he was afflicted by blindness when the Warped Ones attacked. Subsequently, there was no follow-up to "clear" that area properly.
If non-evil, non-chaotic characters had entered the Sepulchre the ancient programmed illusion would have been triggered. The Sword of Delir the Brave would have been obtained by its natural wielder, Jibran. Who would have subsequently dealt +4d6 damage to pretty much everything encountered in the adventure, afterwards.
In addition everyone in the Sepulchre when the sword is claimed by a worthy owner gets a Bless spell lasting 24 hours.
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What if...the Tombs of the Lesser Caliphs had been checked out?
Maybe slightly less probable due to the party's general clockwise exploration of the palace grounds. You might have decided to check the place out while waiting for the barrier to come down, as you had some spare time.
You might still have ended up passing it on to the Janni at the end of the adventure because "cultural treasure", or you might by then have felt otherwise, but you'd have had a +4 (+6 against evils) bow that did +2d6 damage to pretty much everyone in the place.
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What if...Jess hadn't had/used a Wand of Secret Door detection?
Your party are pretty much shit at Search. Even Sunaeco isn't that good - he's just not that kind of Rogue, really.
All the secret doors in the Palace are DC 30 to find. You might be able to make DC 30 with some "Assists" but it becomes likely that you wouldn't have found them all right away. The secret treasury would have taken longer to find.
Jess might have started by using the Wand in the first chamber beneath the Treasury instead of the second. You'd then have found the other secret door (that you never found, in the end) leading to...the west side of the Pyglock Warrens. The only exit from there the Pyglocks knew of was the way up into the Palace Kitchens (and fun with Ug'Thamus the huge hezrou chef).
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What if...the Palace encounter had gone differently?
Every DM when they plan an encounter has an idea of how they think it might go. With this encounter, I set it up with several possibilities in mind.
Thezzakondrumas' motives were - he wanted to keep the barrier up and keep control of the Golden Palace. He actually didn't want the invasion to happen at all because some other bigshot from Pandemonium would have usurped him. If he could present the Marshal of the Host of Eternal Night with evidence of the following - a dead Rakshasa, and the heads party of adventurers who killed him - he could claim that the barrier wasn't now coming down, but that it wasn't his fault.
In the event of the barrier coming down, however, and if it couldn't be stopped - both of which were true facts by the time you went into the palace to speak to him - he wanted to destroy the mirror (if he became aware that was an option, which would have been news to him). He would then "make for the hills" and slowly try to raise a new kingdom of his own and army to conquer this world, unopposed by any of his rivals in Pandemonium.
So ironically, his motives aligned with those of the party, and had he known this he would have given you the diamond - but after he'd "screwed around with you for a bit". He wasn't going to hand it to you in a private audience where you could jump him. But he didn't want to show weakness in front of his subjects, so he would have "tested" you.
That was my pre-thinking about it. So, essentially, I had several "most likely" possibilities in mind -
1) The party just attack in a frontal assault. I suspected this would be a bruising encounter. I wasn't wrong.
2) The party infiltrate and scout the palace to determine threats and plan for them or perhaps pre-eliminate them, then attack.
3) The party attempt Diplomacy with Thezzakondrumas and make a convincing argument why he should hand them the diamond, but because he doesn't want to look like a complete pussy he challenges them to "fight my champion" for the privilege. This is what he was about to do, but he didn't get the words out of his mouth before Thorbjorn attacked.
The champion fight would have been, I guess, Thorbjorn against Hignir the fiendish frost giant. There is a "moment" when Hignir looks at Thorbjorn and, though he feels strangely angered at the sight of this Norseman, he also wishes he did not have to fight him, because he is the closest thing to "home" he has seen in a thousand years.
4) Last but not least: "You have some mighty fine dancers, but I am sure your best dancer cannot compare to ours." Cue Berinanya / Cerys dance-off. Everyone loses their minds at Cerys' performance, per usual. Thezza too challenging to turn into a fanatic but he can be convincingly bluffed that Cerys will definitely want to sleep with him if he loans the party the diamond. (Which she wouldn't, in the end - she isn't above a little transactional intimacy when the mood takes her but she is discerning about who she is willing to grace with her favours).
HOWEVER there is something to be said for taking the palace-dwellers on in combat. If you hadn't taken them out when you did, some of them would have still been around for the final battle! They would see the dragon fly out when the barrier came down and realise that if they don't hit you and Gilgamesh' crew while you're off-balance then they'll be next. So they would have come out and joined the fight.
NOT ALL though, because a bunch of them "wink out" when the barrier falls.
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What if...the Mirror of Chinvat hadn't been destroyed?
Three ways in which that could have happened (besides "ooops we killed Godratt" as previously mentioned).
A) After Rescuing Sunaeco, the party had gotten what they came for, essentially. The party could then have holed up, waited for the Barrier to come down, and then Cerys could open a Gate back to Oerth.
B) The party could have tried to get the diamond, but failed.
C) The ritual to destroy the Mirror could have failed (a bit against the odds given the way the buffs stacked up on that but still not impossible)
As you saw, a massive Chaos invasion was going to pour through the Chinvat Gate. That started when you were already in there. General Mastopheles & his good old devil boys stopped the first thrust of that invasion - though without them in play you could still have holed up in a Magnificent Mansion. However, the devils could not have halted the invasion alone; if the Mirror hadn't been destroyed, the invasion force on the other side of the portal would have brought into play some more powerful assets who would blow through the Ice Devil's walls of ice in no time (Cerys' Wall of Force only lasted 20 rounds), and then eventually Mastopheles et al would have been overwhelmed.
Then, when the barrier went down, Gilgamesh and allies would have faced Azi-Dahaka at the head of a Chaos Army, rather than as a lone enemy, which would have put a whole different complexion on the final battle.
IT GETS WORSE. While the Mirror of Chinvat is still extant, creatures coming through it regenerate 1/4 of their starting hit points each round (on top of any existing Reg or Fast Healing they may have). The only way to stop this regeneration is for them to take damage from creatures who are from a plane other than the plane the Chinvat Gate is on. Azi-Dahaka for instance would have had Regenerate 146 (plus his Fast Healing 10).
You may not have immediately cared, of course. But once Gilgamesh' world is overrun, that becomes a bridgehead for a wider invasion of all the Prime Material worlds.
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Overall - though some of the things the party did (or didn't do) may have been sub-optimal, these were compensated for by some jammy / clever actions that swung things heavily in your favour. So, a job well done, in the end.
