This will be the first of many mini-articles that I'm putting out for Warmachine. The purpose of these articles is to teach players all the "tricks" that each faction can put out. Keep in mind that I'll only speak from the factions and warcasters that I have experience with. By experience, I mean combat experience either on the table or in Vassal. You won't find any theory hammer here.
Oh and yes, I'm also going to need your input on how I can format this better. For now, I'll start with the warcasters and what kind of units you'll see with them.
Playstyle: Massive ranged damage.
Feat: The first time a model takes damage in his control area, it's at half armor.
Gimmick: The complete and utter destruction of the opposing army on feat turn.
Units: Defenders, Stormclad, Rangers
On feat turn, Siege and his army can wipe out an entire opposing army. Every single model taking damage will be at half armor means that ATGM will be doing straight dice to Khador 'jacks. A Stormclad will be hitting at dice +9 and each POW10 Electro-leap will be killing any infantry around him. Ground Pounder will also do massive amounts of damage to infantry coming in range of Siege and on feat turn, it's going to absolutely destroy shield walls. Due to Siege's fantastic assortment of spells, he can make Defenders do magical AOE3 shots and give his ranged army constant cover and immunity to blast damage. Mage Sight reveals stealth and Foxhole can drop enemy 'jacks into a hole and open LoS to the enemy caster for ranged assassination.
Playstyle: Using spells to move units into advantageous positions.
Feat: She controls the order of activations of enemy models in her control range. Those models effected have to forfeit their movement or combat action.
Gimmick: Jack Bullet or Bullet Jack.
Units: Defender, Stormclad, Stormblades, Lancer
eHaley has the ability to inflict massive damage to your opponents and then deny them any chance of retaliation. Her Feat allows her to control the order of activations for your opponent's models and they have to either forfeit their movement or combat action. That's absolutely huge; especially if nothing is in combat reach. You can also use her feat to completely deny your opponent's chances of an assassination or successful jack kill. With Telekensis and Temporal Acceleration, she can launch her Stormclad at her opponents with a threat range of 16" with Reach. This is her ideal jack bullet and her other is the Defender. By casting TA on the Defender and moving stuff around with TK, the Defender can claim a aiming bonus with two boosted shots at the enemy warcaster for an assassination. Haley also likes to run with Stormblades because she has access to Deadeye and can increase their chances to hit dramatically.
Playstyle: Ranged assassination and massive single-target damage.
Feat: For each shot that hits, Caine gets +1 accumulative damage to his POW12 guns. Models that are boxed explodes for AOE3 POW10 blast damage.
Gimmick: 19" threat range from clear line of sight or 18.5" without for his ranged assassination.
Units: Rangers, Reinholdt, Squire, eEyriss
There's a lot of eCaine lists out there that play differently from each other. Some take advantage of knockdowns to open up a shooting lane and others compensate Caine's shootiness with melee. Whatever it is, the list almost always feature Rangers, Reinholdt, Squire and eEyriss. The reason why is because Ranger's mark boosts Caine's RAT to an appalling 11 and eEyriss makes sure focus camping warcasters are no problem. On Feat turn with 10 shots thanks to ROF Infinity guns, Caine can move 7" and shoot 12" for massive amounts of damage on a single-target. It's pretty much capable of killing anything in the game with average dice, no exaggeration. If line of sight or shooting lanes isn't an option for Caine, he'll just charge up 10.5" and then Gate Crash teleport 8" into your hiding warcaster's face. Sure, it takes some focus to do so, but 7 shots with Feat is still enough to kill most warcasters in one go. With this in mind, nothing in the game is truly safe from Caine as long as he's alive.
Playstyle: Infantry heavy, combat assassination
Feat: After everything activates, models in control range can advance 3" and make an additional melee attack.
Gimmick: 17" charge range, Positive Charge, Rebuke
Units: Ol'Rowdy, Stormclad, Lancer, infantry by choice
eStryker plays very differently compared to every other Cygnar warcaster. He prefers heavy infantry lists, close combat warjacks such as the Stormclad or Ol'Rowdy, and frequently likes to assassinate in close combat. With Velocity and a clear charge lane, Stryker has a 17" threat range with Overcharge. Overcharge allows him to roll 1-3 D6 and exchange HP for raw damage. With 2 dice, he's hitting for POW22 and using his focus to boost attack rolls on the enemy caster for an an easy kill. Positive Charge makes the Stormclad MAT9 with POW21 and infantry models within the Stormclad's reach gain the same +2/2 bonus. For this reason, you'll see eStryker lists running Sword Knights, Stormguard/blades and Precursor Knights. It's quite easy for these infantry to charge in and do massive amounts of accurate damage when in range of a jack. In terms of jacks, a Lancer is a must for Rebuke since denying enemy orders to a unit for a turn can be game-changing. Ol'Rowdy is also a fantastic buy for a melee jack because of Stryker's affinity.
Playstyle: Accurate ranged superiority.
Feat: Everything in her control range gets boosted ranged attack rolls and models in her battlegroup gets to make additional ranged attacks.
Gimmick: She's RAT8 with a RNG14, POW12 Weapon Master weapon that can be extended to 16".
Units: Defender, Cyclone, Hunter, Stormblades
The first time Kara hits home with a shot, you're going to feel it. Her POW12 Weapon Master gun can be boosted for 12+4d6 worth of damage. With Reinholdt, she gets 2 shots of these from up to 16" range thanks to Fire Group. The Defenders and the Hunters in her battlegroup can claim a lot more opportunities to shoot thanks to the extended range and on feat turn, they're definitely going to find their mark. Kara's feat also allows everything in her battlegroup to make additional ranged attacks that can pummel enemy jacks into oblivion. The rest of her army comp is pretty standard; ATGM with a Cyclone UA'd, B13 and/or melee units like Stormblades to take advantage of Deadeye. With RAT8, Deadeye and Feat, Kara can preform a high-powered ranged assassination from even greater distances than Caine.
Playstyle: Buffing his jacks to unbelievable levels.
Feat: Each warjack in Nemo's battlegroup in his control area gets up to 3 focus.
Gimmick: On feat turn, all of his jacks go buck wild with Energizer and plow through things.
Units: Hammersmith, Stormclad, Ironclad, Thunderhead
eNemo is THE warjack caster in the Cygnar army. His Energizer can make all the warjacks in his battlegroup advance an extra 3"; his Fail Safe can make warjacks with disabled systems ignore their handicaps; Polarity Shield can keep enemies from charging and Lightning Sword turns any jack into a Stormclad with +2 STR and Electro-leap. On feat turn, Nemo gives all his jacks 3 focus so he can have up to 9 by himself to do other stuff; like re-arranging all his upkeep spells and use Energizer. To make things even more interesting, Nemo can allocate focus during his activation and retrieve any focus he put on his warjacks. The applications to this is near endless as it gives Nemo plenty of spell versatility and strategy on how he wants to execute his turn. To keep things even more interesting, Nemo's basic ranged attack now functions the same way as Voltaic Snare (as pNemo). This in itself can cause massive problems for opposing jack armies.
Alright mans, this is all the experience I have with Cygnar warcasters. Most of my experiences come with eCaine, Siege and eHaley but I've recently been playing with eStryker and Kara Sloan. I like them all a lot, but I find the first 3 to be my favorite (especially Caine). In terms of power, everyone except for Kara is considered to be Cygnar's "Big 4"; meaning they're Tier1 casters. Kara is viewed as a weaker version of Siege but I don't see it that way. I think she brings a lot to the table and her playstyle is truly unique.