With the introduction of Shadowbane: Throne of Oblivion, various changes have been made to existing game mechanics for the betterment of game play and to alleviate performance issues.  The basic changes are the following but you can scroll down for additional details on each change:

• City and Fortress Assets can only be built on a City Grid
• Buildings of War (Bulwarks and Siege Tents) can be built on a City Zone
• Buildings of War can only be placed by the Attacking and Defending Nations
• Buildings of War are limited in quantity
• A Nation is limited to how many Bane Circles it can have placed at one time
• Fortress Assets are invulnerable until a Bane Circle is active and in the War Phase
• Nations can purchase Bane Circles of various rank which include protection slots that can be used only on Buildings of War
• Players can only place a Bane Circle that is equal or greater than the Rank of the Tree of Life they are laying Siege to
• Errant Guilds can no longer place Bane Circles

Only 'Buildings of War' can be placed off the city grid

• Previously, players can build any building off of the city grid; now that ability is limited to Buildings of War only
• Banes are allowed to be placed within a CITY ZONE, but NOT a CITY GRID
• Defenders can place up to 4 Buildings of War within their city grid
• Siege Engineers can be slotted in an Inn

Buildings of War are limited in placement locations and quantity

• Buildings of War can ONLY be built next to a city with a Bane Circle on it - and that Bane Circle must match the Nation's bane
• Each Bane Circle can only support a certain number of Buildings of War - more powerful Bane Circles have been introduced, which will have more hit points, and support more Buildings of War.

A Nation is limited to how many Banes Circles it can place at one time

• A Nation cannot have more than three Bane Circles placed at one time
• Any Nation Member trying to place a bane, while the cap is reached, will get a message stating "Your nation is already at war, and your limit has been reached" and will not lose the Bane Circle deed.
• A Nation Member who successfully places a Bane Circle will get the following message "Your nation is now at war in X number of locations, you have X number of banes available."

Fortress Assets (walls, barracks) will  be invulnerable unless the Bane Circle is in the War Phase

• Only City Assets not protected by the Runemaster will be vulnerable during non-siege hours
• This protection wears off during the War Phase of the Bane

Players can purchase different, tougher banes for more money

• Bane Circles now have 8 ranks (a Rank 8 Bane Circle must be used when laying siege to a Capital City)
• The amount of protection slots allowed will be based upon the rank of the Bane Circle.

Only Buildings of War can be slotted for protection in a Bane Circle

• Only items flagged for Siege, i.e., Buildings of War, will be given protection from a Bane Circle
• Only members of the Attacking Nation can place a Building of War and receive protection

Players can only place a Bane Circle that is equal or greater than the Rank of the Tree of Life they are laying Siege to

• When placing a Bane Circle, the Bane Circle must be equal to or greater than the Rank of the Tree of Life of the City to be sieged when placed
• The Rank-checked is only done when placing the Bane Circle so if the Tree of Life ranks up after the Bane Circle is placed and the Tree of Life is now greater in Rank than the Bane Circle, the Bane Circle is still valid

Errant Guilds can no longer place Bane Circles to take over a City

• Only Nations can place Bane Circles; an Errant Guild will have to join a Nation to lay siege to a city