Here are general tips for playing the Empire Campaign in Warhammer: Mark of Chaos on HARD Difficulty. A list of all our Warhammer: Mark of Chaos articles can be found here.
We won't be hand-holding you through absolutely everything, but instead just give tips on situations that we found tricky or that you might not have considered.
Chapter 1: The Call of War
Mission 3: Green Dawn (optional)
Same tactics as before. Focus on getting Armour for Von Kessel, with Tenacity, then saving points for Armoured from the Combat tree. His armour should be 7, or 9 with Armour of Contempt, and enough to easily survive melee without fear of losing too much HP as long as he is supported by handgunners and fireballs from the Bright Wizard. For this mission went with as many handgunners as we could.
Refill your regiments before going in and your barrages and Volleys should be pretty devastating and help you win. Fireball whenever you can to soften up the enemy but don't immediately charge into battle to help Von Kessel if he doesn't need it.
Against the Giant, you can either go around the west and avoid it, or attack. Detach both heroes and attack it, but really you are just buying time for your three regiments of handgunners to shoot it to death.
For the orc camp, fireball the nearest regiment and retreat (or if the regiments move, pull back until they turn back). Try to pull just one or two regiments. The Night Goblins can poison, but this doesn't seem to do much to Von Kessel so make sure he is in front. There is no particular urgency to engage them in melee as the Captain should have enough armour to survive getting shot at.
This is the last chance to buy items in the current store as it will change after the Erstedorf mission.