Plot line and world outline, DM eyes only

The last three nations, mostly two fight over the hinterlands, wherein lies the world tree, which is said to sprout from the corpse of an ancient god, holds eternal wealth of the land and great power, The Hinterlands are a hardy calm people but when roused to wrath, it is difficult to calm them, Astol and Nostrous desire this tree as their new center of the world, to make their empires eternal, but other forces may desire it as well.
Janus, The Lightbringer: Leader of the Hinterlands Confederacy, head of the crusade against the Beastial Hordes

Janus and Wife(Lisandra)

Janus Returning home from the crusade in the southlands

Janus the Lightbringer, after the death of his wife and children I ask of you my warriors of light, should my campaign truly end here? There is so much more to avenge!
When The Last Storm of the Jotunn Breaks, and my hope with it, The Twin Souled Serpents will fall silent and the Heavens weep, for on wings of fire, of light, of metal, will the world end, and Annam All-Father have his vengeance. -Last words of Annam All-Father, recorded only in the Northern Bastion, beneath The Eternal Storm
beastlord conquers, demons arise, angels descend, Bahamut/Tiamat ends the world, Dark lord comes for his creations, Stop the End of the world The Beast arises, From Hell, Unto Heaven, The Storm Breaks, The End, The Beginning, The End Part2

Astol and Nostrus are the two big countries, no mans land between them never allowed to form a real country. Astol is magic based and generally vibes with peace, seemingly infinite resources, ruled by a King and his 7 councilors/guards. Nostrus is an Empire ruled by a dark emperor, generally vibes with war and industry, blackens the land with pollution, set up like America/early England where it is prosperous as long as it expands/takes from the land.

Possible Prelude: You all, for one reason or another one year before game start, come together for WHATEVER reason to take a job, your all contacted and asked to deal with a bandit problem, repel the next attack, and find their base, either through tracking the retreating bandits or capturing one. Failure can happen, if they fail they have to repel a second attack, after which if the party survives they either get a map from one of the  dead of the local area, with possible landmark spots to check, or if they stomp, a defector, saying some weird shits goin on and this aint a normal job, some weird shits happening, and there is a crazy gnoll and his troop paying us to fuck with the locals, not normal raids and shit, but real lower their defenses kinda shit. Then head to bandit base and attack, its a significant threat, but can be beaten with stealth, terror tactics, or sufficient luck/power. The Gnoll troop makes sure the bandits cannot leave, if you attack the gnolls after this is made clear the bandits will turn on them, if you manage to catch the Gnoll leader in any way, you get to fight and take out the feral Gnoll outrider, making the later encounter easier, and guaranteeing an early level lead 1 greater than normal. No documents on anyone, but players can draw their own conclusions, surviving bandits or bandit notes/diaries make it clear they were taking down outposts and making the terrain harder the navigate, though they dont know why, if no one searches the camp they must guess on their own. Janus and Lissandra gave them the job and pay, because they cannot defend the village AND take down the bandits. Then 1-3 years pass depending on if the players killed the outrider Gnoll, with death meaning a longer reprieve to train and repair the villages

Angelic Construct Primal Sin, the holder of all of mankinds old sins, Degraded and cracked with age

The Beast himself, Dragoon and Dragon Rider, gifted with control over beasts by a powerful spell

Gnoll warlord and his feral brother, the outriders of the Beast
The Beast Awakens: From the deep south comes a tide of beasts and beast like races, rolling over all before them, attempting to take the land of Origin for themselves, Astol and Nostrus wish to keep the Root of All from them. The invaders are merciless and varied, with the main force coming soon behind them on the back of wyverns and dragons. Led by a man who claims to be Axion the Beast Lord, He wishes to burn the World Tree, thus ruining any claim on it, and ensuring Nostrous and Astol crumble, but it would also blacken the lands and ruin the life around it. Astol ruled by the Shining King Astalos and his Seven Companions. Nostrus ruled by Emperor Kaius, guarded by his Black Guard. Begin as joint task force assigned to clear out warlords, third party attacks near end. Party fights off or backs off, both sides blame the other for a few weeks but the raids continue until the party or someone important realises its not the other side. The beast army advances and both sides get ready to turtle up, but cant quite hack it because of the fear the other side will take advantage, thus, preventing them from stripping their eastern\western borders for the south. The party is then tasked with scouting into the southlands and fighting back forces, to find out who is leading this mass migration. They will find a staging ground being prepared by the advance army, led by the Gnoll Lord Graius. He is preparing the way for the army of wyverns and drakes and his lord Axion, all convinced this is for the best, so the world may be reset, and its people saved from starvation and extinction in the long run. If killed or if staging grounds burned Axion will launch one last attack on the tree, for while his forces are mighty they are limited, unable to truly contest the two empires, its up to the party and Janus(who will in this fight become known as the lightbringer) to stop them in time for the two kingdoms to crush the forces, or all is lost. Janus will then lead a crusade down south to crush the nesting grounds while the party reaps the rewards.

Hell Arises: Dark clouds cluster in the skies every day for months, starting soon after the Beast is defeated, eventually villages and outposts near Astol begin going dark. Players investigate the disappearances ala the collectors(mass effect) and find blood and torn corpses everywhere, Janus as well as he remains a liaison and hopefully friend. Once bright and peaceful woods now Dark and filled with ominous silence, players investigate and find the pattern in villages with map, all in a rough circle around Astol. Tracing out the pattern if continued will lead them to the fact its a massive mystic symbol of some kind around the local branch of the kingdom, likely intended to do something terrible to the king and his capital. When they go to the next village to intercept/stop them they encounter corrupted men and vile bandits, as well as a smattering of Demons and Dragon corrupted men. Or they decide to just report it and move on and are likely but not 100% forced to go anyway, if so they are told later that the enemy has been routed but that the attacks have only stepped up. Either way they discover that the bandits/evil men are wearing dated Nostrian uniforms, from history checks or after the battle where Astolian soldiers come to cleanup and investigate. They are sent to Nostrous as envoys/Escorts to the Envoys depending on if any are from Nostrous. There they are recieved and upon explaining the emperor looks at them seriously and takes them away with him, to the halls of history, explaining the history of Nostrous and the founding of it out of harsh lands by the first Emperor, the greatest leader they've ever had, other than the current one. Eventually leading them to the walkway to the Immortal Bastion, the Vault of Fallen Emperors. It is explained this is where the past leaders of Nostrous lay, and recently it has become active, there is an old legend that the founder would return in our darkest hour to lead us to salvation once more. Recently his tomb was found to have been burst open from the inside, as well as that of his companions, the original Scourges of Nostrous. Since then the Immortal Bastion has closed itself off, radiating a deep blue/green light into the sky, we can no longer enter. While in Nostrous the party can uncover how the risen fled, through secret passes out of the Bastion. When they come to report this they find the Emperor on his gates being addressed over the city by one of the Scourges, who claims to serve the Founder of Nostrous and demands that now that preperations have been made he step down and allow the true Emperor to take over once more. The regning emperor denies him, telling him to surrender and serve the new regime, that his time is passed, when he denies him he has his men shoot him, which the Scourge swats out of the air and walks into the woods, saying the Reckoning will come regardless of his pathetic cling to power. The Emperor will have the passages guarded and sets the task force to find the Scourges and the Undead Former Emperor and kill him. Venturing back to Astol and informing them, they get ready for war with Nostrous if needed, for this is their fault, and all deaths' lain at their doors. But the King claims that while he will defend his own and avenge attacks as needed, peace is preferable, and he is willing to let diplomacy take its time, as he knows the Emperor of Nostrous will not capitulate. Cleanse these demons and dark forces from our lands, stop them from their actions, and i will not retaliate to this attack, you will have the help of Astol in this, but know that failure is not an option, for war WILL follow. So the party goes out and with Janus and his followers, his army of the veterens from the beast wars, goes out and follows the pattern, fighting demons and saving villages, not being able to stop multiple at once, until there is only 5 left, five villages in the pattern, in each one they will find a Scourge, in time to see the main force leave, not in time to save the people. unless they head to to one village ahead of the advance in time, in which case they must defend the attackers and kill a scourge, either way Scourges die. At the end they find the final Scourge and the founder of Nostrous at last, as his army of Demons retreats into the woods, yelling to the party that he does what he does to summon the end of Astol, so that Nostrous may prosper, but if he may not save his people first, then all must still be saved, the tree WILL burn, and millions will starve. His army retreating to begin the attacking and burning of the World Tree. The party will have to race to stop him, or report back, as Janus races nonetheless to save his home town around the base, and his family. When the players arrive either with Janus or with the Crownsguard and some men, they find the city already taken, and its people being sacrificed, they must attack into the town and massacre their way to the base, where the Emperor waits on the platform, and the final Scourge/s await to stop them, as they fight Janus's family is sacrificed to complete the ritual and the tree begins to burn. The Emperor then comes down and screams IF YOU THINK YOU CAN PROTECT THIS WORLD, THEN COME HEROES, STOP ME, NO MATTER THE CONSEQUENCES. His final words if heard are, I did all I did for the people, for the future, Seek Strength Young Heroes, and the rest will follow.

Heaven Descends: 2 years have passed, and Janus is missing, if the party kept up with him they know he was growing more distant with time, more withdrawn with the death of his family, more and more throwing himself into his work, purging remaining pockets of demons and beasts and keeping Astol and Nostrous from coming in and desecrating the lands. The Party, now presumably friends if they weren't already, are asked by the Emperor of Nostrous to find him, for while this suits his plans without Janus war is inevitable, and he believes Diplomacy is almost complete, of the nations sharing the Tree and its bounty. Unknown to him and the party, depending on whether the Party had made good friends with Janus and convinced him(DC25) to find something new after the death of his family or some variation of it, Janus has either been taken and forcibly possessed by the Celestial Dragon, Guardian of Astol at the behest of the Immortal King(If he was convinced by party), or went willingly so as to end the conflict and end his own pain, and to save the world in his mind, making it all worth it. It is at this point that Night goes away, and only day remains. The King of Astol will then let loose his ancient magics to release the Celestial Dragon but unbarring the Doors of the Heavens, allowing Janus, now possessed, to lead his existing crusader army North to find the remains of the lost Kingdom of Astora. Unbeknownst to the Ancient King Angelic Hordes will descend and possess the King, turning him into even more a demigod warrior to break free of Astol and lead the Angels to the tree, for they need a lynchpin to maintain their forms on this world marked against them. Astol and Nostrous have begun their war now, as Astol launches strikes and descending angels massacre Nostrous citizens to make the path easier, for this is their last chance to prevent the prophecy. Players are asked by the Emperor of one of his Scourges(or any NPC of Nostrous they've bonded with), to kill the Angels in the city while the army is gathered and the Scourges march, for without them the Army will have to be diverted to protect its people and the Tree will be lost. the party does so and then has to rush to catch up to the Emperor(or they decide not to and he loses, damming the world to the starvation of billions). When they arrive they have to fight through the hordes with the help of the Army and the Scourges, holding off a few Planetars, maybe even killing one(wounded?), before arriving at the base of the tree where the The King is forging the bodies of Planetars into a sword to cut down the tree. He turns to fight them, sending the Planetars to hold of the Scourges, as he cannot take them by himself unless some died, then the party fights him and kills him, causing the hordes lynchpin to unravel and return to the Heavens, all weeping in sorrow and apologizing to the humans for their failure. The Ancient King breathes his last, saying he has made many mistakes, but none more so than sending Janus North, his people will not understand, his knights will want revenge, and open War with Nostrous is inevitable, but the party NEEDS to head north to stop Janus, he is making a mistake, he WILL cause the end of the world. The Eternal Storm is not what we think, it is no simple weather phenomena, it is the prelude to a curse, when it breaks, and it will, an ancient curse will be unleashed, and the tree will whither, millions will die as resources dry up.
The Storm Breaks: The party must race to stop Janus, either fight or stealth through his army of crusaders to The Base of the Dragons Spine, the largest mountain range in the world and home of The Eternal Storm, where they will either successfully forge through the storm to find the Bastion, or get lost and surrounded by Janus army. Brought before the Fabled Last Bastion by their own power or Janus, they must get inside, either stealth or a lightning raid, as the army is too large unless they bury the valley in an avalanche. Once inside the throne room they find Janus and his elite Guard, as well as several mages, attempting to break open the frozen solid Giant at the center of the room, locked in black ice. If captured the party has a chance to convince Janus that breaking the storm is the wrong thing to do, it will unleash a terrible curse. He is convinced semi easily(DC20), but says that the Storm is being drained to maintain this prison of True Ice on the Storm Giant at the Center. To keep the storm from going out eventually they must reverse the ritual Janus was intending and free the Powerful Jotun Prince. If entering under their own power the party can continue the assault and attempt to kill Janus, who either keeps them distracted with his minions while the mages work or cracks the True Ice with his final blow, or they can attempt the same persuasion as before. Either way it comes out that the Celestial Dragon was actually the lingering spirit of a powerful True Giant, or Jotun, who has bided his time for thousands of years guiding Astol to the point where they would send someone north, to unleash the last hope of Jotun Kind from his Dragon Induced Slumber. The Party will then have to fight the Jotun unleashed from the ice as he proclaims he will tear down the Mortal nations and perfidious dragon worshippers in thee name of Restoring Astora to its rightful glory, those that live will be made slaves. The Party fights him and likely kills him, either because he is old and not as strong as them or because they are fresh and have Janus help, or a level up if needed. When the Giant dies the ancient text above the throne shifts to common, to be read by all the true prophecy of the end, and if alive Janus(Possessed) reveals his treachery. Its too late he says, my revenge is complete and the world is doomed. The party then decides what to do with him or reads the prophecy and heads home as the storm breaks.
The End: The final war for the tree is beginning and already casualties are massive, the Emperor of Nostrous and his Scourges taking the field alongside the army vs the Shining Knights of Astol, out for revenge for the murder of their King and guiding light. As the battle rages, wherever the party is, involved or not, the Tree will pulse and glow and fire white blue energy into the night sky, and deep into the earth through its roots. From the Ground will emerge in great fire and rage Tiamat, angry and red as she burns the tree and lays waste to the armies. Shortly there after the party will see the pulse of energy reach the moon, and in a massive blast crack it, where upon Bahamut the Platinum Dragon will crack it open like an egg and emerge in all his glory, raining fire and magic down upon the capital cities of the world. The Immortal King of Astol will teleport the party too him on a distant plateau, explaining that the tree was not the boon they had thought, but the root of an ancient curse laid upon the world by the Father of Giantkind, in revenge for the Dragons victory in the war. None of them are strong enough to defeat the Twin Gods of Dragonkind, but the party is the worlds only hope, he says he has enough power to delay this, if he finally truly sacrifices his immortal soul to one who has wanted it for oh so long(Asmodeus), he can send the party to the world that was, to an alternate world ruled by an evil tyrant, The Immortal King had he been less Benevolent in his desires. Defeat him, claim what power you can, and the timeline will collapse in on itself, hopeful through this you will gain enough power to stop The Twin Gods, for you surely cannot now. As the Emperor of Nostrous rages and fights the Twin Gods they fire their breath weapons at each other, meeting in the middle and exploding outwards to sear the lands, as the fire begins to wash towards the party the Ancient King sends them off with a small speech to Asmodeus, and in a flash of hellish light they are gone, as the world Ends around them.
The Immortal King: The party comes too around the base of the Tree, blackened and burnt, surrounded by stunned soldiers, who attack at normal initiative. They scream about revenants and returning to hell once more, seemingly in genuine panic, if captured they will spill the beans on what happened in confusion, until the party dispatches them. The forest around them is devastated and chopped down, skeletons and rotting corpses strewn about. The Shining King Astolous, decided that The Yggdrasil was tainted and must be burnt and destroyed, once he did so and defeated the Emperor of Nostrous the Angelic Legions that came to aid him departed, standing in the ashes of the tree its spirit engulfed him and he declared he had made a mistake, it was not the tree that was corrupted, it was the worshippers of the Dragons, and they should be purged, as that was the official gods of Astol, that was all citizens. The party of the time tried to stop him, along with Janus the Lightbringer, however they were defeated by the King and his Shining Knights. The King converted Janus to his side and left him here to man the garrison and root out the survivors and traitors, and then did similar stringing his Knights across the lands to catch up to him and slaughter in his wake, as he heads off into the wider world to continue to kill his new enemies. The party must decide whether to kill the knights along their way, or go right after Astolous, if they go right after Astolous the timeline will collapse back into Quantum Certainty and the party wont be strong enough to kill both Gods, but will have to try, maybe marshalling survivors. If they decide to kill his knights and Janus they will fully level to 20. Generally 1 per knight. When finally confronting Astolous, it will be in the Armory city of Hast, the place where the crown made and stored magical weapons and armor. Fight before or after looting/sneaking the party will have time to do so. When confronted the possessed king will say you will fail now just as you did then, Annam All Father will have his revenge no matter the timeline. When the King dies after a day the Timeline collapses, removing its horrors.
Godfall: The Party returns to just after the blast had hit, finding the scorched corpse of the King Astolous, pointing west, where they can see Tiamat rampaging in the Capital of Astoulous, cracking a barrier held around the keep, of Bahamut the only sign is the scorched and flattened city of Nostrous. The party must decide to go after Tiamat or Bahamut. They should have a number of magic items by now, gained from mid and end bossess of arcs, maybe a few legendary items, but if nothing else should Tiamat be defeated then they will each receive a legendary item, as she tells them her dearest wish is to see Bahamut dead, and that bastard All-Fathers curse wasted and averted, even if it means letting the people of this blighted world live.
The Party must then consult those holding out in the Bastion of Light, finding it to be a horribly burned Emperor Nostrous and his Scourge Leader, as well as 2 Shining Knights, the only survivors of the opening salvo. They tell the party they're surprised to see them alive, which the party can explain or not. Then after some rest and figuring shit out they can convene and make a plan to find Bahamut, either waiting on the Shining Knights to successfully tele-scry an answer and sacrifice themselves to form a barrier, or do a faster but riskier play and go to the Immortal Bastion of Nostrous and use the Planescope within, to find Bahamuts exact Location, and use the souls of the dead of the day to power a barrier keeping him there for the party to attack. If the latter is chosen the fight begins immediately, if the former it begins after 3 days and the population falls below 1 Billion as unlike Tiamat Bahamut is not sadistic, and wishes to spare suffering where he can, so he is efficient about the slaughter. Once he is dead the party faces a new world, one deprived of people, as Bahamut lays dead and dying, his final words being a heartfelt thank you for ending the curse, as he says he will do what he can to atone for this curse, and heal the world, as unlike Tiamat he fades away, and new life springs from his corpse, creating an eternal spring around him, spreading through the world and renewing life, so that never again may people suffer from such hardships as starvation and hunger.
The Party has succeeded(or not), and the world is saved, ready to begin anew, and may decide its new direction. They then decide what they personally wish to do in this new world, as the game ends.