IMHO the most major differences between the first generation of TW games (STW/MTW) and the second generation (RTW/M2TW) is the campaign map. You will either love it or hate it. The MTW map is a kind of Risk type provincial map. With counters that are dragged and dropped from one province to another. If you drop your army into an enemy province, it's an invasion, and an act of war, simple as that. There is no strategic manouvering on the campaign map in STW or MTW, it is for movement of entire armies, construction, training, management and diplomacy (movement of agents) only. If you've come from RTW and liked the RTW campaign map game, and also played RTS or Civ type games prior to that, you may find the MTW Risk style map rather disappointing.
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