[quote=caliban22]
Unit wise what Are we talking? Will chaos marines have ways to A. Traitor guardsmens/cultists B.a way to produce ships to enlarge fleets/ create new ones/replace loses
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Depends on your planets, chaos can be entirely cultists and traitor guard. This is not tabletop it is entirely fluff based. Traitor guard can choose to have no cultists or other traitors or choose to have them in droves.

The ability to produce new ships will be difficult for everyone. The RP will likely start with a forge world able to produce battleships under attack by a waaagh and sending out an open distress signal/