User blog comment:Meta07/Walfasized E.Wars Characters/@comment-4814638-20140316180235

"Her family name, 大太刀 ("oodachi" or "noodachi") is the coolest, longest, and most lethal kind of katana, and is also one of the strongest if not THE very strongest Japanese sword."

According to TVTropes, there's something even bigger called a "zanbato". Usually made only to demonstrate forging techniques (forging as in "making something out of metal", not "making a fake copy of something"), these things get up to five metres long.