The info below is a bit out of date as it refers to the beta. If you happen to be looking for an up-to-date reference for your Dragonknight, I suggest this eso guide . It includes some killer advice on leveling up, builds, skill rotation, and gold farming.
The Dragonknight class in The Elder Scrolls Online will be one that mainly concentrates on melee DPS as well as tanking. They will most likely be the main tanking elder scrolls online class of the game due to the skills they have available. They also utilize a solid number of abilities that have magical effects.
Dragonknight tanks will want to focus primarily on the Draconic Power skill line, which where is where the majority of their tanking abilities and passives will be. Active abilities such as Spike Armor, Inhale and Reflective Scales will be vital for reflecting damage and preventing damage. Dragon Blood is the Dragonknight’s self-heal and heal-over-time ability that will also be vital.
The Dragonknight gains access to some extremely important tanking passives in the same skill line. Iron Skin increases block while Burning Heart boosts the amount of healing you receive. Elder Dragon increases health regeneration and Scaled Armor increases spell resistance. All of this will most likely be mandatory for endgame tanking. The Draconic Power ultimate ability is called Dragon Leap and is a leap attack that deals massive area-of-effect damage as well as performs a knockback. This will be a great way to open combat.
As far as other Dragonknight abilities go, the Ardent Flame skill line as well as the Earthen Heart skill line both have some interesting options. Fiery Reach, which is in the Ardent Flame tree, will most likely be vital for tanks as it can be used to pull an enemy directly toward you. Other Ardent Flame abilities include damage-over-time effects and area-of-effect attacks. These may be useful if you’re looking to go the route of a tank that can also deal serious damage.
In the Earthen Heart skill line, Dragonknights can choose earth-based attacks and buffs that serve a more supportive nature. Obsidian Shield is a damage absorption shield that looks like it may be particularly useful for tanks. Ash Cloud can also be used to cause enemies to miss more frequently, which will be useful. The Earthen Heart ultimate, which is called Magma Armor, will also be useful as it will lower the amount of incoming damage significantly.
Since the Dragonknight can be built offensive or defensive, tanks will be able to choose which direction to go in based on their favored playstyle. Once we know how difficult endgame encounters will be in TESO we can begin to speculate as to which builds will be the most prominent.
The info above is a bit out of date as it refers to the beta. If you happen to be looking for an up-to-date reference for your Dragonknight, I suggest this walkthrough . It includes some killer advice on leveling up, builds, skill rotation, and gold farming.