Dragonstone, sometimes referred to as the Kingdom in the Narrow Sea, is a faction located east of Kings Landing on three Islands and two Peninsulas in the Narrow Sea. It is ruled over by King Stannis Baratheon. It's main city is Dragonstone.
Dragonstone is the smallest of all the factions contending for the Iron Throne. Dragonstone's largest advantages is it's location in the sea, bottlenecked Peninsulas and it's heavy units that can defeat most other faction's in a seabattle. Dragonstone's victory relies heavily on quick land grabs and the larger factions distracting each other.
Dragonstone troops are dressed in black. Like the Vale, their levies can be upgraded into halberdiers, which also unlocks bow-armed troops at Tier 3. Levies they can also be upgraded to men-at-arms similar to those used by The Stormlands and The Westerlands, which can be upgraded to Serjeants and Household Guard at higher tiers. These halberdiers are excellent at breaking through heavy armor (a major challenge for lower-level troops or players). However, due to their lack of shields, they will fall rather quickly to missile fire and in prolonged melees. A common Dragonstone battle strategy is to put men at arms (with shield and sword) in the first rank, halberdiers in the second, and archers in the third. While the archers disrupt charges and harass the enemy, the men-at-arms absorb both arrows and the impact of a charge. The halberdiers then move in, using their longer weapons to hammer down on the enemy forces pinned by the men-at-arms. Knights and other armored cavalry can be quickly disposed of this way.
Dragonstone and it's two other islands were given to Stannis Baratheon following the Baratheon victory in the War of the Usurper. After Stannis declared war on the Iron Throne many Crownlander Lords joined his cause. Such as Ser Justin Massey and Lord Roger Staunton.