"Baal is overrun with hundreds of Tyranid splinter fleets. The Blood Angels recall all their successor chapter to aid the homeworld, all who come losing their Chapter Masters during the fight. As all is thought lost and Commander Dante prepares to die fighting, Guilliman arrives to break the last Tyranid forces – with possible aid from the daemonic forces of Khorne!" <-- in what book did this happen!?!?!?!