Finally, on 0605.010M42 the much anticipated invasion of Bastien got underway. Supported by Dreyer's battlegroup Apocalypse as well as the cruisers Relentless and Imperious, the mighty Imperial force jumped into the Bastien system to find no Chaos fleet awaiting them. Admiral Thok had clearly been delayed and fears of a space battle in the chaos system came to nothing. With the path ahead of them clear the first strike units of the invasion reached the planet just two days later.
On Bastien the Claws of Lorek, with their Anticross allies who had just managed to arrive before the Imperial fleet prepared to meet the 18th Army Group as it deployed some 500,000 troops in the initial assault. The could not know where the hammer would fall but confidence in their ability to thwart an Imperial invasion, which as yet had no support from Astartes forces, was high.
Veers had put Major General James Petraeus in overall command of the first strike and the choice of landing zone was made to favour his heavy armoured units. The first troop landers made planetfall without contest in the far north of Bastien's habitable zone, away from the frigid deserts of the planet's polar regions. Under the weak heat of the system's red dwarf star which coloured the sky a baleful red, Petraeus' armoured units moved south to the heavily fortified settlement known to the traitors as Heretic. Here the Claws of Lorek had spent some time building a set of fortresses facing the shores of the acidic ocean which dominates the planet's equatorial region. To their rear a set of "impenetrable" craggy hills would, so the forces of chaos thought, prevent Heretic ever being taken from the north. They were wrong.
Thanks to Imperial spies and months of careful groundwork, the Imperial commanders had found a way through the barren hills to the north of the chaos city, and combining air assault and armoured power, the city fell alarmingly quickly after a violent fight. With Heretic secure Petraeus immediately swung his armoured thrust west towards Vaden across the rolling savannah and deserts of northern Bastien. Taken almost completely by surprise at the shambolic fall of Heretic the newly arrived Anticross forces who were only now deploying along the Vaden-Heretic highway were utterly routed, leading to a total collapse of all other chaos forces in the northern plains. Much of the population loyal to the chaos forces now began a headlong retreat to the next large fortified city, while those who remained in towns and smaller cities along the Vaden highway now had to face the Inquisition, who had accompanied the invasion in force. By 1205.010M42 the Imperial battlegroup had landed a million men and were just fifty miles from their second objective.
While the second invasion wave prepared for planetfall scheduled for 1505.010M42, Lorek himself began organising his defences. The initial phase of the campaign had gone badly, but the forces of Chaos had yet to employ the greater part of their forces who were mostly concentrated around the capital, Bastien Primus, a city of one billion souls. For the population in the north, their new masters were no more forgiving than their old ones. In fact, in just one week, fully one third of the population in Heretic and in settlements on the northern plain were put to death for crimes of heresy, witchraft or mutancy, either by Inquisition death squads or by newly created and fanatical Imperial cults. In places anarchy reigned, with the Imperial agents merely arming the new "loyalist" forces in what was becoming a bitter civil war.