you have to kill also all knights inside the village and castle

-maybe, I have not tested it- if you kill all knights outside twice (2nd after respawn) it will count too

Recently played it and promoted my dragon successfully.

Some thoughts
- You just missed one who is out there hiding somewhere. :^)
- Sometimes enemies who are wounded can run away off the edge of the map. They can wander around out there, but you can't (it triggers the travel dialog). If you leave and come back they'll be in their starting position again, but with full HP, of course.

Hey, friends. Thanks for your response.

I'm pretty sure I killed all the knights, including the ones in the village and castle. I completed the quest from Jerin Flame-Eye (to kill all the knights), and he says he'll mention it to Deftclaw Redreaver for the promotion to Great Wyrm. But when I go to see Deftclaw, there's no dialogue. So, because I can't get the promotion, I can't advice my Dragon to Grandmaster.

In the end, it's not a big deal in life. Just annoying.

Thanks again!

Deleted my previous post as I just worked this out.

You need to go visit Deftclaw in the Merchants guild in Ravenshore, that is why he says nothing to you in his cave - he 'shouldnt be there'.

Deftclaw will only go to Ravenshore if you ally with the dragons. If you ally with the knights, then he won't go to Ravenshore. It is, however, an idea about what happened.

Also, did you make sure and kill all of the trained dragons that are in the dragon slayer's camp? I think they count too.

Sorry to necro this thread but this is indeed a major bug in the game. it does not matter that you did indeed kill all the dragon-slayers/knights and you have Whistlebone sword equipped when you enter the dragon cave and talk to the leader. I just went through this and now have to abandon the game after days and days and days of playing to get this far. At first I thought maybe Deftclaw Redreaver was in a different location than the caves because when you go to the caves it says only "Ilsigore;s(spelling?) cave" and when you enter that you get only "Thanks for the help!" (which I think might be for completing the dragonbane flower quest early on). On all the web sites I can find it says Deftclaw is in the dragon caves in Garote Gorge but I will look around some more and see if there is anyway he is somewhere else.
According the various web sites there are many such bugs in this game (some of which are complete game enders).

-Is the sword equipped to a character (they are holding it) or is it in a character's inventory?

-Have you allied with the Dragons? If so, Deftclaw isn't anywhere in Garrote Gorge for the entire rest of the game.

-Which cave(s) have you visited when trying to turn in the quest to get promoted?

Edit:
In addition, being unable to turn in the promotion quest is far from a game stopper. There are two dragons that have already been promoted. You can add the promoted dragons to your party later in the game. People have beaten the game without ever using a dragon at all.

Yes of course it is. I always consult online walkthroughs and information sites for these games before I declare something buggy. I know all of this stuff. I have not allied with anyone yet. The dragon caves in Garote Gorge. I know all of that but there are some RPCs that I have no problem dismissing and hiring replacements for (such as that knight you can replace with the 50th level knight fairly early on (I plan on doing it around level 30-35 though many others seem to do this way before that) but the dragons are not really like that from what I read. Apparently by the time you can get those other dragons the dragon you start with will be way better. Plus I kind of get attached to characters I put all this effort into developing.

I asked about the sword, because I've always had the sword in my inventory when I went to turn in the quest. I've never had an issue completing this particular quest.

Not being able to find the right dragon, and the name you provided for the particular cave seems wrong, might have been a point of failure for someone unfamiliar with the game, which is why I asked.

I can totally understand getting attached to characters, though. I don't know if the later dragons (or later versions of any character class) are really all that much better than the initial versions. On my "One Day:" list is "Compare each character in each class and see who comes out ahead in skill points".

Never mind. The reason I could not find the actual cave of "Deftclaw" (and kept mixing it up with Klain Scarwing's cave) was because of the atrocious graphics (which I love; don't get me wrong.) and questionable level design. I never cast Wizard Eye in friendly towns so it never occurred to me that Deftclaw's room might be pretty much hidden from view . You almost have to be running into the wall before you notice there is a sloping passage below.

I can see from old internet posts that I am not alone in this error so I don't feel like a complete jackass ("Just a normal jackoff..." as Squisgar would say).

2 Talen1976: (sorry, I didn't know how to delete this test message, so here it goes). I have recently been stuck with this ridiculous bug and this nearly killed my willingness to carry on with the game. On the good side of it, I could make it. Whether you're still with us or not, my next post will provide a step-by-step instruction (it's a good thing to know it's not going to be longish).

Here are some points of uncertain but potential importance. My first topic-related savegame was made inside the Dragon Hunter's Camp after "clean-up". We had reclaimed the Sword of Wistlebone before, but it was not in my hero's inventory at the savegame time. My hero was operating alone and was under the Fly spell. Lloyd Beacons had been set in Garrote Gorge and Murmurwoods.

Now that's it.

Get Town Portal'ed to Ravenshore, fly to the Merchant House of Alvar's door, enter it, approach the Council Chamber Door, knock on it, address Deftclaw Redreaver for promotion and be asked: "Have you slain the 'Dragon Slayers'? Where is the sword of Wistlebone the Slayer?!?"

Turn around, go out, fly to the Adventurer's Inn, grab the Sword of Wistlebone from the one who is keeping it, fly back to the Merchant House of Alvar's door, enter it, approach the Council Chamber Door, knock on it, address Deftclaw Redreaver for promotion and be asked again whether you have slain the "Dragon Slayers" and where the sword of Wistlebone the Slayer is. Turn around and go out.

Lloyd Beacon to Murmurwoods, cast Invisible, fly up to the western border, then turn 90 deg down southward and keep flying until no enemy mark can be seen on the mini-map.

Lloyd Beacon to Garrote Gorge.

From Garrote Gorge, get Town Portal'ed to Ravenshore, report to Deftclaw Redreaver – and Jane's your aunty.

Frankly, easier done than written. Perhaps there are easier ways, but finding them was not my intention – at least, not this time around.

This bug happens because you give the dragon leader the egg before you clear out the Whistlebone quest (kill all the soldiers on the map, and particularly the hunters at the tents in the SW corner). You can't talk to the dragon leader once you hand him the egg.

But all is not lost. You just sided with the dragons, so when you complete the other two mainline quests (save the minotaurs in Balthazar's Lair and side with the clerics or nercomancers), you go back to Alvar, speak to the guy in the building just NE of the armor / weapons / magic area, and he tells you to go see the council in the Alvar government building.

In there, you see representatives of the factions you allied with, plus the Alvar leader. When you click on the dragon leader, you can finish the Whistlebone quest and promote your dragons to grandmaster status. Just make sure you finish the Whistlebone quest and get your dragons skills to level 10 in case another glitch occurs.

I realize this is an old post, but if someone has this issue in the future, there are actually two separate quests.

One (the dragon promotion) is to get the sword and kill the dragonslayers and tamed dragons out in the field, and the other is to kill all of the dragonslayers (i.e. in the field, in town and in the castle).

You turn in the sword to Deftclaw Redreaver for the dragon promotion, and you talk to Jerin Flame-eye once you've killed every last dragonslayer (which involves killing every dragonslayer at Whistlebone's camp, the outer field area with the tamed dragons, in the town, and the castle, including the interior castle treasury area and what looks like a passage down into a crypt).

It doesn't appear to be bugged, although perhaps it has been fixed since.

Confirmed: I tested the dragon promotion quest with two groups, one pre-alliance and one post-alliance where I sided against the dragons, and it worked as described above, although perhaps there's a bug if you side with the dragons as someone mentioned, I don't know.