Hokh-Man offered the Undead a decided advantage over Grogger's force. The damned heat (-1 to Speed when charging, excluding Shambling) limited Goblin mobility. Meanwhile, the power of Ophidia (+2 to all spells) empowered an already-dangerous Jarvis and his loyal mounted Necromancer. The Undead were able to easily surge through sand dunes (difficult terrain; see: brown bases in the accompanying pictures) and control the battlefield.
The Undead surged forward, while the Goblins were slowed by the heat and terrain. Grogger may have overcompensated on his left flank, placing both hordes of Trolls to deal with the Werewolves and Barrow Wights. While the Trolls regenerative abilities allowed them to go toe-to-toe with the Undead, this meant that the middle of the Goblin line lacked any heavy hitters to back up the cowardly, disposable Sharpsticks. The Trolls also could have used an Inspiring presence, as they found themselves wavering early (Nerve check of 10 + 7 wounds -1 from Brew of Courage = 16 with Nerve 14/17) and unable to counter the Undead assault. Their regenerative abilities extended the battle, but they were unable to stop the Werewolves or the Barrow Wights.
The Goblins' left flank was unable to stand up to Jarvis's Wraiths and Revenant Cavalry. Jarvis was able to avenge his previous humiliation, as his forces slaughtered all of Grogger's Mawbeast packs. The Goblins still had a chance of slowing the Undead advance, as two War Trombones fired 24 total shots into the Revenant Cavalry. However, they only managed 5 wounds, and the Revenant Cavalry held (Nerve check of 3). This allowed the Undead to tear through the Goblin war machines and into the center of the battlefield.
In the middle of the Goblin line, Grogger's poor deployment left him with no counter for the Undead's powerful Revenant horde. Grogger's Goons and the remaining Sharpsticks were overwhelmed from all angles. Grogger and his lone Wiz were the only survivors, fleeing for their lives as they cursed Jarvis and vowed revenge.
FINAL THOUGHTS: Poor deployment doomed the Goblins. The Trolls found themselves stranded on the flanks, leaving cowardly Sharpsticks to maintain the Goblin line. The Trolls Regeneration allowed them to withstand damage from the Barrow Wights and Werewolves--once healing an entire turn worth of wounds to return to full health. However, their low Nerve value eventually saw them wavered and unable to retaliate in a decisive fashion. On the other flank, three Mawbeast packs were methodically taken apart by Wraiths and Revenant Cavalry. The Goblins final chance to salvage a draw disappeared when the War Trambones unleashed two dozen attacks to no effect. The Undead were then free to pick off the remaining Goblin units and converge on the center of the battlefield.