Do I HAVE to type this example for the twentieth time? I'm actually starting to get tired of it...
Lady Nimue of the Lake is basically an Arthurian equivalent of the Water Fairies in other folklores; she blessed Excalibur with her magic, which enabled Arthur to slay the dragon. The sword used by his predecessor, Uther Pendragon, was also blessed by a fairy.
Brinsingamen, Freja/Freya's necklace was blessed by the king of the dwarves, it offers protection against various evil spirits and other magical creatures (AKA dragons)
Druandal was literally wielded by a Dragonslayer, and it was blessed, again, by a fairy.
Basically, Magic > Dragons, which is generally true in almost all forms of media.