Summoned units disappear after the battle. The chaos lord that turns is another issue I hadn't thought about ... fluff wise you would expect it to stay, but game-play wise I know that is a big part of the khornate lists and what makes them function and I don't want to handicap by limiting that ... I would lean towards saying that for the terms of this campaign that form is a temporary blessing of Khorne and that they revert to their chaos lord form after the battle, just as I don't want to hinder the daemonkin players in particular. Any objections to or thoughts about that for anybody?