A custom battle lets the user decide all of the conditions and what factions they want. There are a preset amount of maps all varying from forests to open grass plains. When a user sets it up they have variants to choose from, such as the time of day, the weather, the difficulty, etc.
The player also has the option of doing sieges of whatever they wants from wooden castles (in M2TW) to Huge Cities. A maximum of 8 players (computer or human), and teams are allowed, with two teams for sieges. The player also chooses what faction they are going to be playing as(even normally unplayable factions ex. papal states).
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