Having had mastered the force, the Jedi Knights found that it was too cumbersome to keep expending energy to remain dry in rain. Getting wet was not an option either since Master Yoda had a particular smell that emanated from him once he got wet (reminds me of the time when my Aunt Ella would wash her dogs - an annual ritual). So the Jedis did get to creating this cool umbrella (pricey at 41$ apiece) but with the saber embedded into the handle which would light up when desired. All you knights out there get to choose your own colors which range from red, blue and black.

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