This command can be used to add or remove (use negative numbers to remove) opinion from one empire to another.
add_opinion [source id] [target id] [opinion amount]
|Source ID||The ID of the empire you wish to add opinion FROM. Your empire ID is always 0.|
|Target ID||The ID of the empire you wish to add opinion TO. Your empire ID is always 0.|
|Opinion Amount||The amount of opinion you wish to add, use a negative number to remove opinion.|
add_opinion 3 0 10
This command adds 10 opinion from empire with ID 3 to the empire with ID 0. Your empire always has an ID of 0, so this would add opinion from empire with ID 3 to your empire.
add_opinion 3 0 -10
This command is similar to the one above it, but instead of adding 10 opinion, it removes 10 opinion (because we use '-10' instead of '10').