When the new Lord Discordant was announced it was admitted he was in this artwork. All of the new models depicted in art work have been in very faitfhful poses to their miniature. We can clearly see here there is a new Dark apostle to the left of Abaddon.
Looking at him we can see on his back pack the candle lit piece from the Daemon Rumor engine and in his hand the burning chaos book. I wonder when we see him in full, if the other chaos book will be on him or other rumour engine parts.