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What's the difference between [Houses] and [Sides]? Why does a new side (e.g. Forgotten) needs an entry in [Sides] while it should be enough to add one to Houses and then change in [Sides] "GDI=GDI,Forgotten". Is this only in RA2 possible or in TS too?
Yea, in theory that should work yes? No, TS dont do that for some reason. Ill give you this though.
On the left life the the equals sign you can put anything...
[Sides]
UberNewOwnage=GDI
Just confirming it for everyone

House defines the actual global sides that appear in the game, where sides tells the game what houses are allies and what are enemy's. (in theory again)
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Why does in the original rules.ini [Nod] has Side=GDI and actually no side uses Side=Nod? Why however, does in original maps, Nod has Side=Nod? (In every map i saw, the houses are redefined and beside the additional map tags like Credits for the house, the Side= tag is now set to a different side.)
How do Multiplayer maps even work, since they don't have these changes and use the rules.ini settings with Nod having Side=GDI?
Well, About the Side=GDI on [Nod], It does not seems to have a inpact on the game, as if you put Side=Civilian it will still work fine.
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So why do new houses (sides as we understand them as seperate factions) work in maps and not as a global new house in rules.ini?
Possible they only added code for Maps to allow new sides. But the Rules.ini class only gets a hold of this logic though a mistake on a jump or something.
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What do actually the owner= tags for units/buildings take? Houses or Sides?
String, 128 character limit array, Anything from [Houses]
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I find this very confusing and hope you can help me bring in some light to this.
I try to help where i can