Thanks for the replies.
more comments:
2) Here's where you were being easy on your players, IMO.
A dragon (as many people have mentioned as a reason for them not knowing adventurers that well) doesn't see them that often.
So to NOT buff up with the spells he has is just not being smart. That's pretty straight-forward.
He could have cast Mage Armor, Shield, and Bull's Strength, or Endurance (an extra 21-42 HP's can't hurt) or many others.
Key: It's not like he's saving them for anything ELSE more exciting during the day, do you think?
3) Since he wouldn't cast 2nd level spellsin combat (I agree), than his spells are useless unless you have him use them to attack that day and get lunch (or entertainment, perhaps)
4) So the party knows the dragons's weakness and strenghts, but the dragon doesn't know the party's (reflected in EL?)
5) I meant ANY help the dragon can get. Henchmen, Charmed agents, etc. Many people have put forth good examples why a dragon would not only have himself as a weapon.
6) Now this i think is an oversight.
This adult dragon is on average 150 years old.
150 years!
I'm sure he could have gotten some effective treasure in that much time, considering that adventurers get effective stuff within months of starting their careers.
7) Ya, the dragon still hasn't even had the advantage of home turf (i.e. his DEN)
What are the PC's planning to do? Wander around on the mountain till they find the den?
If they persist, you should have the dragon healed and buffed with plenty of areas where he can actually USE his feats, flying, and burrowing to good effectiveness.
9) He should also have Ventriloquism, right? Not much good unless he learned Common in those 150 years, I guess.
12) I think you should have used the feats more, if possible, or keep them in mind next combat, if there is one.
13) Speaking of the next combat, I think your PC's would be suicidal to try again.
The dragon wouldn't play footsies with them again, and there are 7 left.
It seems to me it would be VERY easy to FlyBy Attack and waste at least 2 or 3 in 'strafing/snatching runs' IF you want to use your dragon's abilities against your PC's.
And that's IF he attacks them alone (which doesn't make sense - he's outnumbered)