The Sword of Vespers

Longsword

A longsword that can be transformed into a whip, and disguised as an ordinary object.

-Iron blade
-Handle is polished birch, wrapped in kid leather.
-Ruby in the hilt.
-The core that runs through it and connects the segments is "battle energy." Basically, it's fueled by negative emotions.

7lbs.

-The user can telepathically turn it from a sword to a whip and back again.
-The sword splits into small segments, and the energy rope can be extended up to 50 feet long or 2 feet short.
-When in whip mode, the segments are poisonous, and can melt armor on contact (think acid).
-Whip mode is explicitly powered by the rage and bitterness of its user. If there's not enough, it will just go back to being a regular sword.
-The energy rope itself is white-hot and will burn anything it touches.