The reals of Chaos are on display from Games Workshop this week as part of their pre-orders. Age of Sigmar gets the big bulk of it, but there's a new Horus mini available as well. For those not following the Chaos gods, there's still the latest issue of White Dwarf that you can pick up.
From the article:
The Mortal Realms tremble this week, as the Slaves to Darkness pour forth to conquer all before them, taking back what’s theirs from Sigmar the pretender. If that’s not what you’re about, you can prepare to fight back with a new Matched Play supplement, while in the Age of Darkness, Horus reaches the peak of his powers.