This is a feature I really like since it means there is a greater scope for specialisation.
The castles also make less money and are harder to capture. Just about the biggest innovation is that settlements can either be castles or cities, with their own set of soldier types and buildings.
The in-game videos of assassination attempts make a welcome return as you see your assassins more often than not bungling their sabotage/murder attempts and meeting a sticky end. The units themselves are richly detailed, showing upgrades on the battlefield such as better armour and the units are no longer the clones they were in Rome: Total War, with different faces, shields and helmets making up realistic-looking troops. The graphics are a major improvement, and although a pretty decent system is needed to show them in their full glory, they can be really spectacular. However the amount of new features more than justifies the decision by Creative Assembly. Medieval II: Total War was seen by some as a backward step since at first glance it appeared to be no more than an update of the original game, when a number of fans were eager to see another era covered.
