Drakreign
An enchanted sword forged long ago by the Noldor in the first war to combat the mighty drakes that the enemy unleashed upon them. Nearly all are destroyed now, however one remains. The sword adds +8 attack against dragons, and is resistant to their fire. However it's true purpose is to disable the dragon completely. If the blade can be stuck into the neck or the back of the mighty beast, the sword's magic will completely desttroy the armour and wound the beast mightily. The Blade is destroyed in the process because the magic that holds it together disperses into the drake after contact.
(note: This is the only way I could figure out how lower level characters could beat a full powered dragon.)
One ring to rule them all, One ring to find them,
One ring to bring them, and in the darkness bind them