The nearest thing to a RTW style multi player campaign ive seen is Pax Romana.The campaing map covers the same regions but has alot more provences and many more factions.The emphasis is on the diplomatic side of things and battles take a somwhat abstract form,a bit like naval battles in RTW but not quite so abstract.Also, only the seven roman factions are playable which means only seven peeps for multiplayer.
Pax Romana was released in a bit of a mess which is a shame in general for this genre.Hopefully the total war series will continue to grow and make develpopers and publishers alike take note and invest in strat games.
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