Board Thread:Warhammer 40k General Discussion/@comment-79.112.147.114-20160201151516/@comment-25507520-20160203170223

Techincally Daemons could merge. And in that regard Avatars of Khaine could as well. Seeing as they are shards of their creater just like Daemons. However there are no documents of this probably because it can only be done inside the Warp itself.