Wondrous Item

Uncommon

A simple blade conceiled in a prosthetic leg.
The blade can be extended and retracted as a Bonus Action.
When the blade is extended for the first time in combat, the first attack made with it has advantage.

Infectious Sword. When you hit a creature with this weapon, you can cast Charm Monster on that creature, once per long rest without expending a spellslot. Until the spell ends, you can use an action to see what the target sees, hear what it hears and talk to it telepathically, as long as the target is within 1000 feet of you. When you are percieving through the target's senses, you are blinded and deafened to your own surroundings.

This weapon uses Charisma for its attack and damage rolls