Mogrok - The Horde Approaches: During the final assault of the long, bloody war, the Orks converged upon Fortress Alaric in their countless millions. This time, their advance was not the uncoordinated, belligerent thrust typical of Warlord Grukk, but a cunningly wrought series of tactics that led the Orks right to the doorstep of the Cadian defenders.Worse still, the threat from the skies was far from over. Castellan Jakren Stein's Cadian Shock Troops were still shoring up the defences that had shuddered out of the slopes of Sacred Mountain when the mass of greenish-black on the horizon came into visual range. A great horde of Ork walkers led the assault, ranging from the size of Ogryns to the size of hab-blocks.Each was waving its weapons, be they giant shears, chainsaws, wrecking balls, massive buzz saws, rock-drills, or a profusion of large-bore guns jutting out from their shoulders and arms. Every one of them had a set of wire-coil horns curving around its head, crackling with barely-harnessed energy.At the heart of the Ork walker horde was the giant effigy the Nobles of Alaric Prime had encountered upon the Great Savannah, the ruin of its missing head replaced with the tusked cab of an armoured Battlewagon. It was escorted on either side by two captured Imperial Knights. They stumbled and lurched like the dead brought to life, the heraldic devices on their carapaces daubed over with crude death's heads that dripped blue paint into the dust.To the east and west alike the Ork hordes were spilling around the foothills of Sacred Mountain. Stein gave his aide, the master of the ordnance, the signal to commence bombardment and strode to the parapet of the Aquila Strongpoint he was using as his base. Within seconds the Basilisks stationed on the lowest foothills of the mountain had spoken. Great plumes of smoke drifted up from each of their Earthshaker Cannons.Stein followed the high parabolas of each artillery squadron's barrage, nodding in approval that the next volley had been fired before the first had even struck home. The smile dropped away from his face when the first set of shells slowed and then stopped in their ascent twenty metres above the Orks, hanging in the air as if they had sunk into some thick, invisible jelly.The second volley thundered down after the first, only to suffer the same fate. The castellan raised his magnoculars, a horrible suspicion dawning as a scattering of live ordnance thickened above the Ork horde.The crackling wire horns attached to each of the walkers -- somehow they were creating some kind of electromagnetic field -- one that repelled falling ordnance as easily as a duralumin rainshield stopped an acid squall. The Orks had robbed the Cadians of their long-range advantage in one fell swoop.A galling half-hour of impotent artillery fire later, the Ork vanguard had piled forward at impressive speed. Mobs of howling xenos had reached the edge of the boiling moat in a dozen different places. As they had covered the last half-kilometre, Lascannon teams had picked out a few of the largest clusters of artillery shells that still hovered high above the Ork walkers. The resultant chain explosions had taken down pockets of Ork vehicles here and there, but hundreds, perhaps thousands more remained.It felt to Stein as though every Greenskin tribe, klan and mob on Alaric Prime had somehow converged on his position at the same time. If they could not rain shells down on the foe, they would have to deliver them via a more direct method. The castellan spat an order into his vox-bead, and the Leman Russ battle tank companies ranged along the length of the boiling moat trundled into position.Three by three they opened fire, each shell raising a wake of white spume across the moat as it thundered towards the approaching Ork horde. Several of the shells exploded amongst the Greenskin ranks with gratifying thumps, but many more detonated prematurely, flame blossoming across invisible hemispheres of force.Guttural laughter drifted up from the plains below, seeming to mock the castellan's pitiful efforts to thin the horde. Somewhere, thought Jakren Stein, there was an Ork war-mechanic begging for a priority kill.