They fought bravely. The Green Dragon was no match for the knight, because he fought with a magic sword, created a long time ago by Archmagus Theor, who hated the eternal good-evil war. There were runes written on it, but no one couldnt understand them. They said: Two enemys, one blood. The Archmagus gave it to two of his students, so they could decide which one of them would take it. It was clear to him, that they would fight for it. The good student was very defensive in the fight, and when the evil one started to be tired, he tried to cheat ant kill his enemy with the Mages sword, but Theor foreseen that and the sword itself dealt with the cheater. His blood never dried.
“How many good things I can do with it!” - the young knight started a crusade, and ended it in Unkh-quasti’s lair, the keep of greatest evil. After killing the dragon, the hero died because of the last poisonous gasp of the dragon. Then, the heroes blood fell on the sword. The blade became red, and the blood of the two students remained forever.
Now the sword is waiting for it’s next owner. Although it’s called The Green Sword, after the dragon, only its hilt is green, the blade is red, and seems to be covered in blood. It exists to destroy all good, or all evil. The sword likes straight alignment, hates neutrality - neutral travellers consider it as an ordinary sword.
One time at a day, you can call the dragons or the knights spirit, depending on your character:
-If you are evil, calling the evil students spirit your enemies will be surrounded by poisonous gas.
-If you are good, calling the good students spirit the sword will strike your enemies with a mighty roar, and they will run away horrified.