Dragons once thrived on the plane of Tarkir. They spawned from mighty elemental storms, filled the sky with their destructive breath, and terrorized the five ancient warrior clans. But the dragons met their fate long ago. For many years, the clans fought a war against the dragons for their own survival, hoping for some way to gain an advantage in the struggle. At a crucial turning point more than a thousand years ago, the dragon tempests stopped coming, and no new dragons were spawned. Their numbers thinned, and the tide of the war changed.
Ultimately, the warriors of the clans were able to hunt down the last of the sky-beasts and destroy them. Dragons were rendered extinct on the plane, never to return. In the centuries that followed, the five warrior clans claimed dominion over Tarkir, growing and evolving into today's powerful clans. Led by the five khans, the clans clash with each other to this day, trampling the land in furious battles. Each khan seeks to win territory from the others - and some wish to rule it all.
Although the clans drove the dragons to extinction, each clan still emulates an aspect of the dragons' nature. The resilient desert warriors of the Abzan clan are known for their endurance, exemplified by their armor made from the scales of fallen dragons. The Jeskai, monks and sages of lake-top monasteries, study the mystical arts and revere the dragons' cunning. The Sultai build luxurious palaces in the jungle murk, echoing the ruthlessness of dragonkind in their empire of undead servants. The fearsome riders of the Mardu crash across the highland wastes with the dragons' speed. And the shamans and survivalists of the Temur have conquered the perils of the icy wilderness by emulating the dragons' savagery. The dragons may be gone, but their memory lives on in each clan's culture, style of warfare, and magic.