Shoshopu did a good job summing everything up! I just wanted to come in and add a few more lore details as well as my own summary. It's difficult to talk strictly about Amdapor without talking about the War of the Magi also. But I'll try to keep it brief.
3,000 years ago, Eorzea was plagued by the Age of Endless Frost, the Fifth Umbral Calamity. The world had frozen over and people were dying to plague, pestilence, famine, and war. It wasn't until magic was invented that could conjure flame without tinder that the Umbral Era ended and gave way to the Fifth Astral Era as mankind was able to survive the cold and the ice eventually receded.
Having used this early form of Thaumaturgy to survive, the Eorzeans sought to develop greater magicks and propel their societies of magi into a golden age - which they succeeded in doing. But one magi in particular was not satisfied with Thaumaturgy's limitation, being that it drew upon the caster's own lifeforce to invoke magic. Being limited in her own aetherial reserves, the magi Shatotto set out to develop a technique that would instead draw aether from a more abundant source: Hydaelyn. This new technique was coined Black Magic, for it killed the land surrounding the caster, but it allowed them near infinite powers.
Fearing this magic developed by the Mhachi civilization would soon grow unchecked, the elementals gifted the civilization of Amdapor their magic of Succor, with which to keep Black Magic in check. For many years, the two existed in balance and harmony. Until, perversions of the arts were made to meet the ever growing destruction caused by Black Magic. It was then the War of the Magi broke out between the White Mages of Amdapor, the Black Mages of Mhachi, and the Scholars of Nym.
For years the war dragged on. Archons of the time tried to stop the Mhachi, but in their greed for ever greater magicks, they turned to the Otherworld - the Void. In exchange for their powers, the Mhachi pulled voidsent through portals and let them lay waste to their enemies. The Voidking Diabolos all but razed the Amdaporians before the White Mages were able to seal him away. But so great was the toll of the war on Hydaelyn that the planet had been completely drained of aether. So in one last desperate attempt to end the war, the elementals summoned a Great Flood, the Sixth Umbral Calamity, to wipe away the taint of magic. And to ensure their magic would not be perverted again, the Elementals grew up the Black Shroud around Amdapor and sealed the city itself away within a great arbor.
Mankind outlawed the use of magic, and its practitioners were hunted down. What few survived returned to the temple of the Mhachi and founded a city of Magi so that all that they learned would not be forgotten. This city was called Belah'dia, the father of Ul'dah and Sil'dih. But White Magic was kept a secret deep within the Shroud, and the knowledge of its continued existence was kept only by the Padjal, a race of the elementals' own creation. It wasn't until the most recent, 7th Umbral Calamity that Amdapor was revealed by a shard of Dalamud tearing through the Amdaporian tree.
As for whether it's dangerous to breath within Amdapor, I'd say prolonged exposure would not be healthy. But the severity of the spores should/could be based on the RP story you wish to tell. If it makes for a more dramatic story, make it so that the spores are particularly thick for whatever reason - perhaps a recent heavy rain or high humidity has caused an increase in spores and for this reason it's particularly difficult to breath. Note, along with the spores, there's likely a ton of ambient aether inside the Lost City, and prolonged exposure to that would cause aethersickness on top of whatever the spores do to your lungs.
(This was actually the original lore behind why there are dungeon timers, by the way. The air in dungeons have increased ambient aether density, which causes extreme sickness if you stay inside too long. Obviously this doesn't apply to all dungeons, like the Vault or Castrum, but places like Toto-Rak, Amdapor, Dzemael Darkhold, etc you could use as part of your story!)
Hope this helps! ^^
3,000 years ago, Eorzea was plagued by the Age of Endless Frost, the Fifth Umbral Calamity. The world had frozen over and people were dying to plague, pestilence, famine, and war. It wasn't until magic was invented that could conjure flame without tinder that the Umbral Era ended and gave way to the Fifth Astral Era as mankind was able to survive the cold and the ice eventually receded.
Having used this early form of Thaumaturgy to survive, the Eorzeans sought to develop greater magicks and propel their societies of magi into a golden age - which they succeeded in doing. But one magi in particular was not satisfied with Thaumaturgy's limitation, being that it drew upon the caster's own lifeforce to invoke magic. Being limited in her own aetherial reserves, the magi Shatotto set out to develop a technique that would instead draw aether from a more abundant source: Hydaelyn. This new technique was coined Black Magic, for it killed the land surrounding the caster, but it allowed them near infinite powers.
Fearing this magic developed by the Mhachi civilization would soon grow unchecked, the elementals gifted the civilization of Amdapor their magic of Succor, with which to keep Black Magic in check. For many years, the two existed in balance and harmony. Until, perversions of the arts were made to meet the ever growing destruction caused by Black Magic. It was then the War of the Magi broke out between the White Mages of Amdapor, the Black Mages of Mhachi, and the Scholars of Nym.
For years the war dragged on. Archons of the time tried to stop the Mhachi, but in their greed for ever greater magicks, they turned to the Otherworld - the Void. In exchange for their powers, the Mhachi pulled voidsent through portals and let them lay waste to their enemies. The Voidking Diabolos all but razed the Amdaporians before the White Mages were able to seal him away. But so great was the toll of the war on Hydaelyn that the planet had been completely drained of aether. So in one last desperate attempt to end the war, the elementals summoned a Great Flood, the Sixth Umbral Calamity, to wipe away the taint of magic. And to ensure their magic would not be perverted again, the Elementals grew up the Black Shroud around Amdapor and sealed the city itself away within a great arbor.
Mankind outlawed the use of magic, and its practitioners were hunted down. What few survived returned to the temple of the Mhachi and founded a city of Magi so that all that they learned would not be forgotten. This city was called Belah'dia, the father of Ul'dah and Sil'dih. But White Magic was kept a secret deep within the Shroud, and the knowledge of its continued existence was kept only by the Padjal, a race of the elementals' own creation. It wasn't until the most recent, 7th Umbral Calamity that Amdapor was revealed by a shard of Dalamud tearing through the Amdaporian tree.
As for whether it's dangerous to breath within Amdapor, I'd say prolonged exposure would not be healthy. But the severity of the spores should/could be based on the RP story you wish to tell. If it makes for a more dramatic story, make it so that the spores are particularly thick for whatever reason - perhaps a recent heavy rain or high humidity has caused an increase in spores and for this reason it's particularly difficult to breath. Note, along with the spores, there's likely a ton of ambient aether inside the Lost City, and prolonged exposure to that would cause aethersickness on top of whatever the spores do to your lungs.
(This was actually the original lore behind why there are dungeon timers, by the way. The air in dungeons have increased ambient aether density, which causes extreme sickness if you stay inside too long. Obviously this doesn't apply to all dungeons, like the Vault or Castrum, but places like Toto-Rak, Amdapor, Dzemael Darkhold, etc you could use as part of your story!)
Hope this helps! ^^
