Lustria
Lustria is a continent in the Warhammer World of Warhammer Fantasy Battle. It is a rough analogue to South America; tellingly, it is primarily inhabited by the Lizardmen, a race of Mayaincatec-styled, reptilian humanoids, as well as unintelligent dinosaurs and snakes. It is mostly covered in inhospitable rainforest host to a menagerie of deadly flora and fauna. The jungle itself was created by the Slann in the time of the Old Ones as a type of natural defense, which explains why its denizens are mainly reptilian and so enthusiastically killy.
Generally speaking, if something in WFB isn't set in the Old World or Ulthuan, it's probably set in Lustria.
Geography & Culture
Geography
Lustria for the most part is a vast jungle, full of deadly plants and creatures. The fluff states that the Lizardmen weren't satisfied with traditional defences to protect their cities, and so made the entire continent a green hell of painful death to protect them instead. The Lizardmen cities are vast temple complexes resembling a mash of Mesoamerican and Inca cultural aesthetics. Being crammed full of relics made of gold and gems the men of the old world go quite crazy over them and regularly expeditions set out to steal everything not bolted down....ummm explore the realm for the good of mankind. Of course the psychic frogs and their minions don't take too kindly to this and most expeditions end up as sacrifices or, worse, lost in the jungle hell of Lustria. As it happens the Lizardmen don't care for the commercial value of their gold, valuing it more for its longevity and thus making it mighty handy for inscribing information for future spawnings.
Culture
The dominant culture was the continent-spanning Lizardmen civilisation. The Lizardmen are led by giant, intelligent, magical frog-men called the Slann, who spend all their time dozing or playing mental chess with each other, the Lizardmen seek to restore order to their broken world the only way Warhammer Fantasy will allow; by sending in armies of giant killing man-lizards and their pet dinosaurs. Their neighbors up to the north are murderous spastic pirate elves.
To be fair, the Slann do do more than just sit around discussing the weather. They spend a lot of time and effort holding the power of chaos at bay that would otherwise flood into the Warhammer world from the realm of Chaos and corrupt everything, making the current grimdark state of things look like a summer picnic. The Slann though, being of 'higher intelligence' don't seem to understand the need to get a move on with things. They spend a lot of time carefully trying to figure out everyone minor point of the great plan of their lost Old One masters that they can waste centuries worrying over an exact sentence, all the while Chaos is invading the house, stealing the tea and making off with the biscuits.
It is not just Lizardmen that inhabit Lustria. There are tells of lost colonies of wild women, the Amazonians, who compete with the lizardmen for the sacred spaces. A variety of other creatures inhabit Lustria and there are many secret beings left undiscovered in the jungles as well.
The north-east coastline of Lustria is known as the Vampire Coast. Centuries before the modern day Warhammer world the vampire Luthor Harkon was shipwrecked on the Lustrian coastline after the ship carrying him was destroyed. Seeing opportunity and using his necromantic arts, Harkon raised the crews of the ships shipwrecked along the coast and made them into his own Pirates of the Carribean inspired zombie navy, complete with zombie parrots! Now Luthor rules over a realm that is the terror of the seas and a thorn in the side of the Slann, who Luthor has been trolling ever since he first stepped foot on the continent.
A whole tribe of the dreaded skaven even arose in Southern Lustria. The forebearers of Clan Pestilens were dying from the tropical diseases when they turned to Nurgle the Horned Rat (in a new aspect) to give them succor from the diseases. In time, the pestilent band of disease loving rat monks were doing what they do best; spreading diseases and destroying several lizardmen cities. When the Lizardmen finally had enough, they did something rather unexpected and created a new snake God to obliterate the skaven. While clan Pestilens didn't retreat from this crude threat, they ultimately decided to return to the colder and murkier old world.
In 2005 Lustria got its own supplement because the environment is so different from the other Warhammer continents, but that was a few editions ago.
The End Times
With the release of the fourth book of The End Times, The End Times: Thanquol, new rules for Lustria-based scenarios were released. New, as in lifted from the previous Lustria campaign supplement and slightly edited.
While for the first few books the Lizardmen were lucky, this shouldn't be mistaken for idleness. During the events leading to Nagash's resurrection, Lord Mazdamundi realized that the Old Ones' plan had failed and began ordering to pack up shop everywhere. To this end, Skinks with golden crests were spawned, who began working on the pyramids.
Fluff-wise, the apocalypse reaches Lustria when the Slann realise that a Daemon incursion is imminent, one even greater than the initial Chaos Incursion (somehow, despite the Polar Warpgates not changing and the Elven Vortex still happily sucking up all the Magic), and set about booby-tapping their already deadly rainforest especially for Daemon-kind. Unfortunately, whilst the Lizardmen do a stellar job at keeping the Daemons at bay, the entirety of the Slaven Clan Pestilens take this opportunity to revenge upon the reptilian folk. The booby traps being bespoke for Daemons, the Skaven manage to slip by with only a few of the rats being blinded here and there. This coincides with all the Slann being knocked comatose in an effort to stop the Skaven Grey Seers from bringing the the bloomin' CHAOS MOON closer to the planet. Cue rampant swarms of rat-men spreading plague, burning forests, and killing Lizardmen like it's going out of fashion.
This all culminates with the Skaven Clan Skyre getting all jealous about the Grey Seers messing with the moon, and decide to just blow it up with a giant cannon. Yep, that happened. Most of the Lizardmen flee in their temple-pyramids-now-spaceships as continent-sized moon fragments rain down. The Slann blow up these fragments with their mind powers whilst blowing up their brains in the process (Which also includes Mazdamundi), and even the mighty Lord Kroak could only barely stop the huge chunks of warpstone meteor before being burned to bits. Following this, what few Slann remained began the process of activating the Exodus Engines (otherwise known as making their pyramids and major cities float) and buggering off to the stars.
Yet again, the Slann save the world and get no credit for it. Only this time they lose their homes in the process. Rude.
The Age of Sigmar release reveals a re-named Lizardmen, now known as Seraphon, that managed to escape the destruction of the world to live in space. Whilst fluff is still being developed for the Seraphon it's safe to say that Lustria is no more.