Why Palpatine HATED Darth Vader’s Blue Jedi Lightsaber

Why Palpatine HATED Darth Vader's Blue Jedi Lightsaber

When Anakin Skywalker turned Sith and became Darth Vader, he still wielded his blue lightsaber as he did when he was a Jedi, now that he had lost it to Obi-wan, Sidious was very pleased.