The first, "Knights and Vassals," brings several new units into the strategy-RPG, while the second, "Legendary Artifacts," contains new missions and class items.

The only thing we don't know is how much they'll run--instead of pricing details, the company provided us with a breakdown of each pack's contents:

Knights and Vassals - DLC

This Downloadable Content requires the base game King Arthur - The Role-playing Wargame in order to play.

About the game
"The legend of the Once and Future King is as ancient as the realm of Britannia itself. It tells about the arrival of a great king who will unite the warring kingdoms of the land and bring peace and prosperity to all."

New units become available after the completion of the "Lady of the Lake" objective:

Briton Archers
Facing constant warfare, the Britons realized that they need some archers who are trained in the art of melee.

Briton Cavalry
These devoted horsemen ride out into the hidden corners of Britannia to bring back rumors. In battles their heavy armor gives them excellent protection, but also slows them down a bit.

New units become available are available after the conquest of either Norfolk or Norgales:

When the Saxons decided to follow the other courts of Britannia and established the knighthood in Norfolk, they only allowed the best warriors to join these ranks.

Welsh Pikemen - unlocked after conquering Norgales
Equipped with a shield and a pike, these tribal warriors from the kingdom of druids are not only good fighters but they are quite resistant to the power of magic.

Two powerful Knights join the Round Table when the first Stronghold is built:

Sir Alymere
This knight was destined to be a great champion and indeed, he became one of the most respected wandering knights.

Sir Lucan
Lucan was a regular participant of the royal tournaments and bravely defended the lands of his family during the chaotic times after the Miracle.

Legendary Artifacts - DLC

This Downloadable Content requires the base game King Arthur - The Role-playing Wargame in order to play.

About the game
"The legend of the Once and Future King is as ancient as the realm of Britannia itself. It tells about the arrival of a great king who will unite the warring kingdoms of the land and bring peace and prosperity to all."

Three sets of unique and ancient artifacts become available. Each set was designed for specific classes: Sages, Champions and Warlords. These artifacts are the rewards of nine challenging and new battle missions.

Sage Set
There was once a blind druid who could rule magic like no one else. When he disappeared, he left his treasured artifacts behind. These personal belongings were thought to be lost...
Staff of the Blind Hermit
Ring of the Blind Hermit
Cloak of the Blind Hermit

Champion Set
Sir Marrick was a knight of King Ryons, one of the greatest warriors of the jousting fields. His pride became the reason for his fall, when he decided to duel with one of the champions of the Sidhe.
Sword of Sir Marrick
Amulet of Sir Marrick
Plate of Sir Marrick

Warlord Set
Gorlois was the Duke of Cornwall, the master of Tintagel Castle. He was a great warlord, but finally he was slain in a combat against Uther Pendragon. His ancient artifacts are said to have magical properties after the Miracle.
Banner of Gorlois
Ring of Gorlois
Armour of Gorlois

We've also got a downloadable demo on FileShack, should you be interested.