Cardboard Katana : Obtained when levelling up the starter Cardboard Sword to max level, +100 speed, +50 coolness, -25 water resistance, when the user is at half health or below they get
How to Make a Lookalike Demon Slayer Sword (Out of Cardboard)
Making a black Nichirin sword from Cardboard | How to make Tanjiro's demon slayer sword - video Dailymotion