A fully mature adult female dragon is the high dragon: the great monster of legend, the rarest of all dragonkind. These dragons hollow out massive lairs for themselves, for they need the space to house their harem of drakes as well as their eggs and the dragonlings.
High dragons are seldom seen. They spend most of their time sleeping and mating, living off the prey their drakes bring back. But once every hundred years or so, the high dragon prepares for clutching by emerging from her lair and taking wing. She will fly far and wide, eating hundreds of animals, most often livestock, over a course of a few weeks and leaving smoldering devastation in her wake. She then returns to her lair to lay her eggs and will not appear in the skies again for another century.
High dragons are impregnated female dragons. Living for more than 1,000 years, these terrifying beasts are known to have at least a dozen male drakes guarding their lair.
At the end of the Blessed Age, many in Thedas believed that all the dragons had vanished until one went on a rampage. A rampage is when one or more high dragons emerge from their underground lair and destroy everything in their path. They gorge, then lay a clutch. [1]
It was this portent that led to the ninth age being named the Dragon Age by the Divine of the Chantry. The dragon's rampage could be seen as far as Ferelden, and the scene of the dragon's rise inspired Loghain Mac Tir to lead his army into victory over the Orlesian army at River Dane.
There are two possible high dragon encounters in Origins (three, if the archdemon counts) and two in Awakening. Please see the relevant quests for details.
This section contains spoilers for: Dragon Age: Origins.
Origins
The Warden is given the option to battle a high dragon during and after The Urn of Sacred Ashes quest. After (optionally) battling Kolgrim and emerging onto the Mountain Top, a short cutscene of a dragon flying above the Warden is seen. The Warden can engage the dragon by using Kolgrim's Horn (PC) or by hitting the gong seen shortly after emerging on the Mountain Top area (X360 and PS3). If the Warden decides to help Kolgrim and follows through, the party won't be able to fight the dragon before killing Kolgrim and his followers. This can be done by speaking to him and selecting the option stating that he is too dangerous to be left alive. When he is slain, the gong can be interacted with again (or the party gains the horn).
In addition to the Mountain Top encounter, the Warden can fight another high dragon if he/she chooses to kill Flemeth in the quest for her grimoire. Flemeth will shapeshift into a high dragon, which must be killed.
Awakening
A third high dragon is encountered near the entrance to Drake's Fall in the Dragonbone Wastes. No items can be obtained from this dragon.
The Queen of the Blackmarsh is a spectral high dragon that can be encountered at Blackmarsh after completing the main quest of that area.
It is possible to fight the dragon without the horn, and possibly even without the gong. If Morrigan, Wynne, or a mage Warden moves behind the cliff the dragon rests upon and looks up in third person mode, it's possible to hit the dragon with Blizzard, which will cause it to leap down and attack. This is untested with other AoE effects, but should work on PS3 and PC with the latest update.
While it probably makes no difference, a party used to achieve this consisted of Morrigan, Wynne, and Shale. Testing was done after completing the Gauntlet.
See a screenshot walkthrough of the map glitch. This is a tricky way to explore that vast map.
See a YouTube video of ambushing the dragon from the cliffs.
(PC tested only) It is possible to call the dragon and kill it without taking any damage whatsoever, with any class chosen. Once you enter the Mountain Top area for the first time there will be two other exits, the Gauntlet and the eastern part of the Ruin. head over to the bridge where you go back into the east ruin. Walk straight to the door (fairly close), and tell you party to hold their ground (H key). At the top of the bridge keep trying Kolgrim's Horn until you are still as far from the battlefield as possible. Once the horn is succesful (even before you spot the dragon) run back down to your party. If done correctly the dragon will be unable to attack you with anything other than buffet which causes no real threat. Equip bows and arrows or just use a mage and attack for a while. Just don't press H again until the dragon is slain. (Might be outdated, the dragon attack "Fire Spit" (note, not same as flame breath) has no problems reaching to the east ruin entrance)
Another option is sometimes if you are playing a mage character and you are stuck under its belly it will freeze in place like it does not see you and just stands there. You can constantly cast AoE spells and not move. The dragon takes damage but will not attack (PS3).
The dragon AI can leave it permanently stuck in a position just to the right of the bridge from the Caverns, between the bridge and the pool of fluid. If you get it there, it will be unable to move or attack and can be taken down easily. This is a collision bug which might be very difficult to trigger, but it has been observed.
(PC tested only)The dragon might get stuck in the gap between the path leading to the east ruin, and the path from where you came. If it is stuck you can circle it, so you are possitioned behind it, and it will not be able to attack you, unless you engage it in melee.
