|Creator||Lady of the Lake|
|Owner||King Arthur (formerly)|
Excalibur also known as Cal, is the former sword of King Arthur, and one of Flynn Carsen's dearest friends.
Sentience: Cal has a mind of his own, and, as such, can choose who he will obey;
Flight: Cal can hover aboveground for as long as he wants to;
Layline Unlocking: Cal will, when inserted into his stone, restore magic to Earth, by charging the Laylines that carry it.
Crown of King Arthur: Any person, good or evil, who has said Crown is able to force Excalibur into submission
The Stone: If Cal is inserted into its stone again, the magic contained inside it will flow into the Earth, causing it to; melt and disappear.
- "The Librarian: Quest for the Spear"
- "The Librarian: Return to King Solomon's Mines"
- "The Librarian: The Curse of the Judas Chalice"
- It was mentioned by Judson to Flynn that only those worthy could pull Excalibur from the stone.
- According to Flynn, wounds inflicted by Excalibur will never heal.
- He is one of the most powerful artifacts in the library, as it was able to contain all magic on Earth for centuries, until shortly after the series started.