Liar's Cane (5e Equipment)
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This weapon does not appear to be anything special, but a typical looking cane, used by those who want to appear "upper class", or those who require some aid while walking. But, to the trained eye, and in the hands of a dexterous individual, can be used to quite a ferocious efficiency. On top of being a quite powerful in the hands of a dexterous individual, the weapon has two other hidden weapon. You have a +1 bonus to attack and damage rolls with this magic weapon.
Forms. This weapon has three forms, the cane form which deals 1d4 bludgeoning damage and has the finesse property, the rapier which deals and additional 1d8 piercing damage, and the whip which deals an additional 2d4 slashing damage.
Transformation. You may change the form of this weapon to any other by using your bonus action.
Thunderous Surprise. When you hit a creature with the cane form, you may use your bonus action to attempt to paralyzed them. The target must make a DC 16 Constitution saving throw to take half of the 2d8 thunder damage and not be paralyzed until the start of your turn. Once a creature has been paralyzed by this effect, they are immune to being paralyzed by this effect for 24 hours.
Dark Coating. As a bonus action, the weapon may gains a dark black obsidian-like glow, which makes the weapon deal an additional 1d4 necrotic damage until the start of your next turn.
The Liar. When making a Deception check while this weapon is in cane form, you make the check at an advantage.