As far as I know, you need to register your game on the website in order to access the multiplayer server.
EDIT: @Tiaexz : You're probably right. Norse music and units are a definite. Not sure about Coat of Arms... I'd love that, but it seems unlikely to me.
Personally I don't buy the unit skins because I am usually so zoomed out on the map that I can't even see them.
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