Excalibur

The is a mighty sword currently wielded by the king of the Kingdom of Camelot, Arthur Pendragon.

Appearance
Excalibur is a broadsword with a very wide blade. The grip has a dark swirly appearance to it, giving the appearance of a cosmic void. The cross guard has a hollow center, and a sharp diamond shape with pointed edges that matches its pommel. The rain guard is adorned with jewels, that emenate with regality.

History
According to Merlin, Excalibur in the past was just a common sword, given to Carfen, a master swordsman. While on the brink of death, he cleansed his sword with his blood and soul. Instead of becoming rusty, the sword became sharper and stronger as it had been infused with Carfen's essence. The blade's next wielder did the same, as did the next wielder of Excalibur. This process repeated countless times over millenia, each knight inheriting Carfen's will and cleansing the sword with their blood in the event of their death before passing it along to its next wielder. After a time, the sword began to choose its wielders, deciding if a person is worthy or not of wielding its might. Excalibur suddenly fell from the sky and was stuck in a huge rock in the Kingdom of Camelot, where people believed that it was a holy sword of God. Many Holy Knights tried to get it out, however, they failed until the appearance of Arthur, who successfully pulled out the sword, and became the new king of Camelot.

Prelude to the New Holy War arc
After Camelot was taken by the Demon Clan and placed under the control of Zeldris of the Ten Commandments, the demon tried unsuccessfully to remove the sword from the ground where it was stuck.

Some time later, Arthur decides to infiltrate the castle to retrieve the sword and use it in battle against the demons. After seeing wounded Cath, and a conversation with Meliodas, who betrayed his friends, an angry Arthur pulls out the Excalibur. Thanks to the power of Excalibur, Arthur manages to avoid the attacks of Chandler and Cusack and cut both in half. Arthur manages to present battle against Zeldris and Meliodas at the same time, getting the upper hand using various sword techniques transmitted to him by the essence of the previous Excalibur bearers.

However, any of them, including Cusack and Chandler gets hurt. In that moment, Arthur falls completely weakened. Cusack tells him that he made a mistakes by abusing the power of the sword without having the power to resist the force of the heroes of the past. Before he could kill Arthur, Merlin appears and manages to take Arthur out. However, Cusack uses his Resonant to force Athur to stab himself with Excalibur.

Abilities
Although many of it's abilities are unknown, Excalibur is a magic sword that won't bestow it's power upon anyone except the one it has chosen. The source of its power is neither from the Demon Clan or the Goddess Clan. It is a divine sword solely of the Humans, imbued with the souls of the master swordsmen who've wielded it in past millennia. Arthur was able to easily overwhelm Cusack, Chandler and Zeldris nearly simultaneously with Excalibur. However this was only through a surprise attack and later on Cusack noted that to properly wield Excalibur, Arthur needed both the power and spirit to fully draw out the sword's power. If the wielder lacks the necessary power then evenutally the sword will become too heavy for them to wield and the spirits of the heroes within it can curl up in fear if sensing the presence of beings too strong for them to cope with.

Techniques

 * A sword technique created by a blind swordman, capable of anticipate and countering any and all manner of surprise attack.


 * A technique belonged to the war king Tartenos, a series of rapid consecutive lunges. His power is capable of sending Zeldris several meters back.