This story is found in King Arthur’s Sword: A Collection of Arthurian Tales
Now amongst his other skills Arthur was a great slayer of Dragons and other monsters. Having rid Britain of such foul creatures he had been asked by Hoel. Duke of Brittany to help him, for Brittany at the time was at the time much cursed with these creatures. Now at a place called Lieue de Greve on the Breton coast there was a particular dragon that was extremely cunning and had resisted all efforts to kill it, or drive it away. It inhabited a great cavern that was so deep, that when it retired into its depths, always being sure to walk backwards in its own tracks, people were fooled into thinking the beast had fled. When Arthur came with a company of his companions to the cave this is just what happened. They camped outside the cave for several days but when there was no sight of the monster they assumed that it had disappeared. They camped some distance away and after many days of checking the cave and finding no sign of the beast they were thinking of leaving and heading back to Britain when one day they saw a sail on the horizon. They soon made out that it was a large coracle, or skin boat, such as had been known in north-west Europe for thousands of years and that it was heading for where they were. When the coracle sailed up directly onto the beach the crew stepped ashore led by a tall, powerful and graceful young man. They came up towards where Arthur and his men stood watching and the young man saluted Arthur saying,” Greetings, can you tell us where this is, My name is Efflam, son of the King of Erin and my companions and I have been driven off our course and have been a long time battling the winds and seas.”
At this Arthur said, ”Well met indeed, cousin. I am Arthur of Britain and this is the shore of Brittany you have landed on. It is good to meet you.” And he stepped forward and embraced the young man who was pleased indeed to have landed among friends.
Then Arthur asked,” Is there anything we can do to help you?”
Efflam looked closely into Arthur’s eyes and appeared to come to some kind of decision. He nodded as if to himself and began to speak. ‘My story is a strange one, cousin. Only a short while ago was I married the fair Enora, a beautiful and intelligent lady, much sought after by many princes. Our fathers have long been at war with each other and saw in our marriage, the promise of peace in the years to come. But neither she nor I wished this. I have devoted much of my life to prayer and contemplation and wished nothing more than to serve Our Lord. On my wedding night I awoke and was overcome with an irresistible urge to leave and find some lonely spot, far from other people and there to make penance. I Know now that this was the Lord telling me what to do. So I rounded up these faithful friends you see here with me and we set sail from home. We ran into wild storms and have ended up here and I am still unsure as to why I am here.”
Arthur was just about to speak when Efflam added. ”Ss we came into shore we saw a great Dragon at the mouth of the cave just along the coast.”
Arthur did not hesitate. “To arms men, he cried,’ and buckling on his sword Excalibur and picking up his lance Ron, said to the young prince.” It is time to be rid of this foul beast. Will you and your companions join us in this battle for this is an uncommon fierce and cunning dragon?”
“Aye willingly’ came the reply and Efflam and his companions got their weapons from the boat and joined Arthur and his men as they quickly headed to the cave.
Just as they were nearing the mouth of the great cave the dragon came running out. It let out a mighty roar that seemed to shake the very sky and the men all flinched and drew back. All but Arthur. He stood his ground as the creature roared. And what a beast it was. Of gigantic stature it was covered all over in great green scales, like armour, its long, thick, black tail was twitching with obvious great strength. In its mouth it had great tusks like those of a wild boar but much bigger and in the middle of its forehead its one red eye glowed balefully at Arthur.
It was truly fearsome sight but Arthur did not flinch and ran at it with his spear. He lunged at the evil creature that swiped at him with a great paw and deflected the thrust. Again he thrust as the beast tried to seize him in its mouth. Back and forward the man and beast moved in their deadly dance, with neither getting an advantage. For fully three days and nights the combat raged but neither was winning. Then the creature broke off and retired into the cave. Arthur fell to his knees, exhausted and slumped against a large rock. Efflam ran up to him.
“Water, water, give me a drink of water,’ croaked Arthur. But there was no water there other than the salt sea water of the ocean, They had come in such a hurry from their camp that they had carried only a little water with them and that was gone, No one had wanted to turn away from the fierce battle that had been going on. And it was clear that the king’s need was great. But Efflam was a man of supreme faith and kneeling there on the shore he began to pray. After a while he rose up and struck the rock three times with the butt of his spear. At that water burst through in a clear bubbling stream. At once Arthur took off his helmet and drank deeply of the clear fresh water. Soon he felt much better and said that it was time to go into the cave after the dragon.
“Cousin,’ said Efflam, ’you have fought long and hard with this foul creature. No one can doubt your bravery and skill. But as you have tried force now let me try and see what can be achieved by prayer.”
Arthur, although quite prepared to fight on, knew just how tired he was and what little chance he would therefore have against the great beast. He was much impressed by the younger man’s strength of character agreed to let him try. So Efflam strode purposefully right to the mouth of the great cavern.
“Come forth spawn of Satan, in the name of the Lord I command you. Come forth now!” he roared. Suddenly the air was filled with what seemed to be the thousand of a thousand hissing serpents and a great shadow filled the cave entrance. Then there in front of the assembled warriors with Arthur leaning on his spear the foul beast staggered out of the cave mouth, howling and spitting blood and vomit from its mouth. It spat at the lone figure there in front of but could come no nearer. It turned away and agonisingly slowly it climbed up the great rock face above the cave. As it climbed the blood spewing from its mouth stained the rock a bright red and to this day it is known as the Red Rock. Then with a final earth-shaking roar the great beast used its last vestige of strength to throw itself into the sea.
As it fell into the waters, they began to swirl and surge like a great whirlpool . There was a thundering noise and the waters rose and tumbled. Then in an instant the waters fell back and all was calm.
But there is price to pay in all things. After Arthur had congratulated Efflam, the young man told him that he had decided to settle in that desolate spot. He and his companions would live a saintly life, apart form the rest of mankind. Arthur, having been impressed by the young man’s holiness, and the power he clearly could summon, gave him his blessing and left with his men to return to Britain. The story has long been told that Efflam and his men were fed by angels in that lonely desert spot and soon after the dragon was slain, those same angels brought Efflam’s lady Enora to be with them. However almost as soon as she had come to that place and been given her own hermit’s cell to live and pray in, her life passed away. When his companions went to tell Efflam what had happened, they found him in his cell and he too was dead. He had been the instrument of a great victory, a victory that had appeared to be beyond even the power of the great King Arthur, but he and his lady, had paid the ultimate price.