Color me interested!

[Edit]

For the ranks, perhaps you could use titles that are used in kendo? Just a suggestion. :3

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Sho-dan - The first dan level can be tested for after 3 months as an i-kyu.
Ni-dan - One full year must be spent as a sho-dan before testing for ni-dan.
San-dan - After two years as a ni-dan, the kendoka may test for san-dan.
Yon-dan - Three years after achieving San-dan testing for this level is allowed.
Go-dan - After four years as a yon-dan, testing is available.
Roku-dan - Five years must be spent as a go-dan before testing.
Nana-dan - Six year as a Roku-dan 
Hachi-dan - 10 years or more must pass before testing for hachi-dan is allowed.
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