Legendary Weapon idea

[Brakelvierr]

I've noticed people have been making these Legendary Weapon threads, so I thought I would throw my hat in the ring.
 
Name: Heiki-ko (Translates to Armoury)
Compatibility:Metal release is required to wield the weapon
Power: Truly a weapon for those who seek to master all types of weapon jutsu or even those who like a blade to fit the play style to which they are accustom to whether it be a small Tanto or a large Nodachi. The weapon is capable of being moulded and shaped in the midst of battle with the potential to become a different weapon entirely. This weapon grants the compatible wielder several jutsu.
The first being a set jutsu that will change it to become different weapons entirely (within the regions of available weapons in the game).
The second being jutsu that make adjustments to parts of the weapon such as length or width of it, maybe even expanding it mid swing or stab.

Personal note: I believe the very chameleon nature of the blade makes it difficult to find the wielder of it, making a trial to find it and increasing the wielders life expectancy/joy ride with it. unless all of the forms were to have a similar appearance such as a massive cringy skull on it then that'd kind of take the difficulty out of finding it.