I had this design done like 1 year ago, and hey why not.

And ehh... well, knowing DK's lore and looking into the concept art/design, someone is up about doing a lore for this weapon? I'll update the description with the best one :D

Lore by ZackFrost:

After honoured Slyrak with the wish to death in combat, the Dragon Knight found that the dragon had sent all its strength and centuries of wisdom to him. He awakens after the wounds on his throat which the claw of the dragon once breaks in to sent its power to him. He felt his body is now full of strength, and the wound on the throat disappear and left no scar behind. Then he looks at the dragon's dead body, and had a thought to forge a sword with the heart of the dragon. As a memento to the dragon, the sword is born, and named as The Dragon's Soul to honor the dragon which gave him such strength to fight for justice.