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Since i only play Singleplayer missions (and some skirmish with AI enemys) i would really like to see a new Campaign.
Did you see this? 
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Mission success and I thought it was enjoyable, so it got me thinking, how about a campaign as a rebel GDI commander
It's not a bad idea, don't get me wrong, but there is the case of fun. If you're playing as a GDI Commander, will that team have new units, new buildings and infantry? etc. Or will this house be exactly the same as, GDI?