From the announcement:
Warhammer 40,000: Dark Vengeance is an incredible new box set that contains everything you need to field your own Warhammer 40,000 force. It includes both a Dark Angels army and a force of Crimson Slaughter Chaos Space Marines, all of which are among the most remarkably detailed miniatures we've ever produced.
Dark Vengeance launches in a limited edition format that contains Interrogator-Chaplain Seraphicus, an exclusive Dark Angels model. This set is available in strictly limited numbers and only Available While Stocks Last, so make sure you head over to games-workshop.com to secure your order today.