Warmachine armies rely heavily on their warcasters. A Warcaster's abilities, spell list, and feat determine how they support their warjacks and troops, so two armies lead by two different warcasters (even different versions of the same warcaster!) will function differently even when the armies are exactly the same.
This article breaks down Khador warcasters according to their main gameplay mechanics.
Infantry
These warcasters make their troops bigger and badder than other warcasters' troops, and with Khadoran troops being what they are, that's saying something.
Kommandant Irusk protects and enhances his troops with spells, making them hard to get to, harder to hit, and harder to kill.
Perhaps the most important spell Irusk has is the Inhospitable Ground Spell that creates difficult terrain for enemy models. Once the enemy makes it through the terrain, they may have to encounter a unit enhanced with the Iron Flesh Spell and made difficult to hit. Then when the need or opportunity arises he uses the Undying Loyalty Feat and Battle Lust Spell to turn his soldiers into tough combat monsters.
The Iron Fang Pikemen Unit or Man-O-War Demo Corps Unit are tough, hard-to-kill models that can take the offensive.
Expanding with Kommandant Irusk
The Dark Champion turns troops into true Khadoran heroes.
The Hand of Fate Spell eases the odds in a model/unit's favor by adding a die roll and dropping the lowest result on attack and damage rolls. Melee troops in his prodigious CTRL area can benefit from the Transference Spell and boost attack/damage rolls by using his focus points. Then when he needs them to hold the line, take the objective, or break the enemy, Vladimir uses the Blood Legacy Feat to give substantial stat boosts to warrior models.
The Iron Fang Uhlans Unit and the Doom Reavers Unit gain huge benefits out of Vlad's spell list and feat since the Doom Reavers don't need to be targeted by a spell to use Transference and the Uhlans charge 14" under the effects of the feat.
Expanding with Epic Vlad
Denial and Control
These warcasters use the power of cold to keep you from doing what you want to do.
Zerkova locks down enemy shooting and charges as her 'jacks protect her from incoming melee.
The Koldun Kommander looks a little soft, but the variety of her spell list is set up to annoy enemies. Her primary defense is her battlegroup, and she uses her Focus Sphere to cast the Watcher Spell at a reduced cost so that her warjacks can move to protect her on her opponent's turn. After that is in place, she uses her other spells to try to trap enemy models with tools such as the Icy Grip Spell that lowers DEF and prevents running and special attacks or the Twister Spell that leaves behind it a cloud effect to block LOS. Then when she really needs to stop the enemy, her Howling Feat removes initial ranged, prevents orders and special actions, so enemy units won't be able to charge and attacks like Thresher won't work.
A start for Zerkova would be to shore up her Battlegroup with Bulldozing warjacks like the Spriggan Warjack or the Devastator Warjack. The Banishing Ward Spell can be used to protect any of her units, such as the Iron Fang Uhlans Unit or a Kayazy Assassins Unit.
Sorscha freezes you with her spells, freezes you with her scythe, and freezes you with her feat.
On the approach, Sorscha has the fog of War Spell to protect her troops and the Wind Rush Spell to raise her own DEF. If her 'jacks get close or need to traverse terrain, she speeds them up with the Boundless Charge Spell. Once she gets into spell range, however, she can cast the Tempest Spell to knockdown models in her way, then use her Icy Gaze Feat to freeze everything in her line of sight inside her control area (since Tempest will knockdown whatever's in the way and it will increase her lines of sight).
The Widowmakers Unit benefit a ton from concealment, increasing their DEF twice due to camouflage. Sorscha can take a War Dog Solo to push her DEF into the 20s against melee attacks. And for 'jacks the Beast-09 warjack and the Destroyer Warjack complement her skills nicely.
Alpha Strike and Maneuver
There's no helping it. Khador is big and tough and armored, but somehow these warcasters always seem to move faster than you.
This spirit of Khador gets her army around the table while trapping yours in place.
Zevanna Agha, the Old Witch, has numerous upkeeps that she uses for movement. She casts the Avatar of slaughter Spell to get extra movement and melee after kills made by herself or her scrapjack. The Unseen Path Spell gets her or her Scrapjack out of trouble by teleporting one of them to the other. She casts the Weald Secrets Spell on a unit to give it the Pathfinder Ability and extra DEF, and while her army is dancing around yours she casts the Murder of Crow Spell to create a damaging template that also blocks line of sight. When she really needs to book it for position, especially against single wound infantry, her Field of Talons Feat makes it very dangerous for them to move without taking a POW 14.
The Greylords Ternion Unit can create cloud templates for the Old Witch to hide in, and solid units like the Iron Fang Pikemen Unit can be made most difficult to hit with the Iron Flesh Spell. Another option is to cast the Weald Secrets Spell on the Kayazy Assassins Unit for a really fast moving counter to infantry.
The epic version of Sorscha moves herself and her Winter Guard up the table and use the power of cold to crack open armor.
Sorscha's Elite Cadre Ability with Winter Guard models give them a reroll for their combined ranged attacks and she can give them additional movement with the Desperate Pace action to overcome the movement penalty she incurs when casts the Iron Flesh Spell on them to protect them. Units close together get taken out when Sorscha puts the Shatter Storm Spell on one of her units, blowing up anything that they kills. The Cyclone Spell catches many off guard when she uses it to charge in. And then she can really hurt something when she uses her Winter's Chill Feat to double damage received by enemies and then casts the Boundless Charge Spell on her warjacks to get them in and break open some shells.
The Winter Guard Infantry Unit and Kovnik Jozef Solo are a good start for Sorscha due to her special rules for them. Shatter Storm is a great spell for shooters like the Widowmakers Unit due to their accurate ranged attacks. And no Sorscha list would be complete with the Beast-09 Warjack to use Winter's Chill to remove warbeasts and warjacks from the table.
Strakhov uses extra movement from his battlegroup to get around the table and then gives his army super movement to reach across the table and axe enemies to death.
The Occultation Spell and his natural immunities give Strakhov defensive options against ranged attacks and certain spells. He then puts the Overrun spell on a battlegroup model that is likely to destroy something in order to position either himself or one of his warjacks closer to the enemy, and then uses the Iron Fist Feat to give most warjacks a charge that can travel 11" (15" for cavalry and 13" for most SPD 6 infantry).
Bulldozing warjacks are wonderful for his feat, and the Spriggan Warjack really abuses this movement by gaining extra Reach and a bonus to hit against models it charges. The Sentry Spell is a good option for the Decimator Warjack given its Beat Back Ability on its gun. Finally, the Kayazy Assassins Unit have ridiculous charge range with the feat and the Kayazy Assassin Underboss Unit Attachment.
The Supreme Kommandant blasts your approach with mortars while his troops stay alive and maneuver themselves over under and through each other and terrain.
Irusk starts off by casting the Fire For Effect Spell on an aoe ranged attacker to cover his army's approach with boosted attack and damage rolls and then puts the Tactical Supremacy Spell on a unit to give them extra movement at the end of the turn. When he needs to get through terrain OR models, he can place the Artifice of Deviation Spell to give his troops supreme movement and trap the enemy in rough terrain. Troops in his command range benefit from the Martial Discipline Ability and gain the Tough Ability so they will even get to move through each other for simply being near him even if their comrades are knocked down from being Tough. Even if he's running multiple warjacks, the Energizer Spell gives them all extra movement. The Desperate Ground Feat stands up his models and prevents models from moving very far or receiving orders.
The Behemoth Warjack, Gun Carriage Battle Engine or Winter Guard Mortar Team Weapon Crew are good targets for Fire For Effect. After that, consider troops of every kind. The Iron Fang Pikemen Unit are a good start, as are the Winter Guard Infantry Unit or Doom Reavers Unit. Really anything infantry is impressive with Irusk.
Warjack Supremacy
These warcasters use warjacks as their primary tools of destruction.
Karchev is a part warjack part warcaster who can efficiently command a multiple heavy battlegroup and run them around the table, tearing things up in melee.
The Man in the Machine uses his Arcantrik Turbine to gain movement or Pathfinder, casts the Tow Spell to move multiple warjacks around when he moves (essentially gaining them extra distance and benefiting from his extra movement and/or pathfinder) and raising their DEF with the Sidearms Spell while they're in base to base. Once close enough to engage, Karchev can bring the 'jacks in to combat with the help of Tow, or if he's close enough, he simply cassts the Unearthly Rage Spell to get boosted melee attack and damage rolls and then launches them with free charges with the Total War Feat. If need be, he himself can use his gun to knockdown models before shooting Khador 'jacks at the enemy.
The Berserker Warjack or Juggernaut Warjack are good choices for cheap melee options. The Spriggan Warjack gives Karchev a heavy warjack with Reach, while the Beast-09 Warjack helps him handle infantry piles. Khadoran mechaniks are a good option to keep Karchev in top shape.
Harkevitch navigates his warjacks through terrain, firing their guns as they go. Once set up, he unleashes them onto the enemy.
The Iron Wolf's battlegroup always has Pathfinder because of him, and he can increase their movement by 2" by casting the Escort Spell. As they approach, he can give his entire battlegroup an extra ranged attack with the Broadside Spell while saving the Jump Start Spell to get his battlegroup moving again after being made stationary or knocked down for the low cost of 1 focus. With Escort up, his entire battlegroup charges across difficult terrain for free for an average 9" charge during the Hour of the Wolf Feat, and if they don't have enough focus to finish the job they're sitting in the enemy's face with extra ARM from the feat.
The Black Ivan Warjack or Behemoth Warjack are both potentially good places to start because of their ranged attacks. Someone looking for stronger direct fire would turn to the Decimator Warjack or the multiple guns of the Demolisher Warjack.
Combined Arms
These warcasters function well with a mix of warjacks, troops and their own strength in arms.
The Butcher increases the damage of his army until he gets close enough to finish the deed himself with his axe, Lola.
Butcher's Full Throttle Spell costs half his focus, but frees up focus on his 'jacks for buying extra attacks since it runs/charges them for free and boosts their attack rolls. The Butcher's "second wave" often receives the Fury Spell in order to deal even more damage in melee. And finally the Butcher's third wave is himself, using the Reach and Weapon Master advantages on his Axe to deliver pure damage that only gets better with the Blood Frenzy Feat as everything in his army (including ranged attacks) gains increased damage.
Full Throttle makes the Berserker Warjack user-friendly since it won't need focus to operate and the Iron Fang Pikemen Unit become difficult to budge with the Iron Flesh Spell on them raising their defense.
Butcher's random, crazier (he got crazier!) and epic version of himself kills everything, and when he kills everything, his army gets better at killing the remains.
The big change to the Butcher are his random focus pool and his ability (requirement) to attack everything that's in a circle around him when he makes a single attack. However, whenever that succeeds, his warjacks become faster and more skilled, and if he kills enough he automatically gets 7 focus on the following turn.When he has the focus to do so, he moves his warjacks with the Boundless Charge Spell or gets extra attacks out of them against infantry with the Ravager Spell. A hand to hand unit can benefit well with the Fury Spell. After he activates his Feel the Hate Feat, the Butcher gains tokens for killed models that allow him to allocate extra movement and attacks to faction models in his army who then get out of activation attacks. So if Butcher doesn't do the job, then his army will.
Epic Butcher's Mad Dogs of War Theme Force is one of the stronger theme forces that emphasizes an abundance of the Doom Reavers Unit. Since his 'jacks get to charge for free, the Butcher can run around with 'jacks like the Spriggan Warjack for its Reach weapon.
The Dark Prince of Umbrey can kill you with his 'jacks, kill you with his troops, OR kill you with his own sword. It just won't all happen on the same turn.
Vladimir Tzepesci protects himself and key models from ranged attacks with the Wind Wall Spell. As his army advances to meet the enemy, he casts the Signs and Portents Spell to help out their attack odds. If someone leaves themselves 10-12" away from Vlad, he can cast the Blood of Kings Spell instead and try to finish things off in combat. Finally, his 'jacks go to town when he uses the Forced March Feat to double their SPD and grant them extra distance with the Boundless Charge Spell.
Mortars love Signs and Portents, and the Dark Prince can get them with the Behemoth Warjack, the Gun Carriage Battle Engine or from the Winter Guard Mortar Team Weapon Crew. In addition, the low accuracy Winter Guard Infantry Unit becomes fierce with odds shifted in their favor.
