You can order your own custom Masamune blade online. Basically any extremely long sword will do, so long as it conforms to certain basics. Most swords sold as "Sephiroth Swords" are really just extra long katanas, renamed Masumune. Do a lot of searching to find the correct sephiroth sword, and the best price.
Wielding Sephiroth's Masamune requires great strength. Sephiroth has this because of the combined Jenova cells and Mako energy inside him. Otherwise wielding such a lengthy blad would be extraordinarily difficult.
An ancient legend tells of Masamune, the swordsmith, who was challenged by his apprentice, Maramasa. Muramasa claimed he could make the strongest sword, and set a competition between the two. They both made their finest swords, then dipped them into a river. Maramasa's blade cut everything that floated past: leaves, fish, debris. Masamun's cut nothing, but instead things gathered around it: including fish, leaves, butterflies. Maramasa proceeded to gloat and claim victory until a Monk approached.
"The first of the swords was by all accounts a fine sword, however it is a blood thirsty, evil blade as it doesn't discriminate as to who or what it will cut. It may just as well be cutting down butterflies as severing heads. The second was by far the finer of the two, as it doesn't needlessly cut that which is innocent and undeserving."
Final Fantasy VII
Final Fantasy University
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