Once upon a time, in a far away land, there was a village. It was small, unassuming, and unimportant. One day, the earth split with a loud crack, and out of the chasm sprang forth mystic energy, which they dubbed "mana." This mana could be controlled by will of thought, easily at that (or so they thought), lending them great prosperity. But the chasm did not stop releasing energy, and in a few years time, the whole world became enveloped in mana.
Thus magic was born into the world.
You, the players, are at the forefront of research into this phenomenon. Armed with little more than a sword and your wits, you set off from your respective tribes on a pilgrimage to where it all began. Naturally, you are not alone, and your journey crosses the agendas of entities high and low. Some may aid you, some may hinder you; watch therefore, and guard your life and knowledge from those who would use it for evil.
The journey is long and arduous, but great power lies at the end of it. Will you persevere to the end?
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Gameplay will be a lot like lorebuilding, except it's all IC. Your characters will be expected to experiment and create new spells, documenting them in a tome. The strength and quality of the spells you can create/cast increases as you approach the Chasm. Additionally, there is another sentient force in the world using magic to create and genetically modify life. This phenomenon should be investigated, and terminated if need be.
Some tribes are more technologically advanced than others; some have developed in different technological pathways. Feel free to come up with creative new tribes to encounter. The highest known tech level is Renaissance, with guns, germ theory, and rudimentary electricity. The lowest tech level is early-Medieval.