Mechanized Walkers
Mechanized Walkers of the Maret family come in two variations: Quadrupedal and Bipedal. Quads tend to be enormous in size, but relatively slow due to their bulk. They make up for this by being able to wield huge armories of mounted weapons and are a force unto themselves. Biped Walkers are usually smaller than Quads, and though they can move slightly faster their main benefit is that they are easier, and cheaper, to construct.
Acacia - Standing anywhere between 3 and 5 meters, Acacia walkers are the most numerous among the Maret forces. They rarely have volatile personalities and often are excited to form a bond with a pilot.
Redwood - Standing between 8 - 12 meters tall, Redwood walkers were once the standard Maret walker, but the expense in creating a Biped walker of such a height, along with the generally abrasive and antagonistic personality they tended towards meant that the Redwoods fell out of favour for most Maret pilots and only a few remain active.
Karst - The original Quad walker, standing at a respectable 5 meters in height, is a staple of the Maret's famous "rolling wave" assault. Karsts (and their pilots) are a commanding presence on the battlefield and many consider it an honour to serve alongside their pilots.
Mesa - A more recent design, the Mesas are usually no more than 10 meters at their highest point but take up a lot of horizontal space. They were a controversial step, and the first group were though to be unusable, as no pilots were able to connect until it was discovered the monumental personalities contained within the machines, requiring incredibly specialized training and fortitude just to talk with the machine. Mesa pilots are the most revered among the walker pilots for this reason.
History
The official story on how the Maret family came to use Walkers as their primary military is that several hundred years ago, a Patriarch named Lorenzo Maret was trying to create a war machine to combat the Laguerre tanks (this fact is highly opposed by Laguerre who created their tanks to oppose the Maret walkers). Unable to find something of significant enough power he prayed to the Lord Sovereign and the Machine he was working on answered him. Thus the first pilot/walker relationship occurred. The voice in the machine instructed him on how to create the Walker Cores and how to connect a pilot to them to bring the walker "to life" in order to accomplish physical feats regular machines would never be capable of.
Since then, Walkers have been a staple of Maret society, functioning in civilian and military roles (though every Walker pilot is a commanding officer in some respect).
Personalities
The specifics of Walker Personalities are still mostly a mystery, even to the Maret. The wide belief is that they are personifications of the Lord Sovereign who guides each pilot in different ways. Others believe they are simply a gift given by the Lord Sovereign as proof of a Pilot's worthiness. Ultimately, there remains no consistent answer, and the personalities themselves have offered no clear answers.
When a pilot first connects to a walker, they must contend with the personality within. For most pilots this introduction takes several hours at minimum, and a connection is not always guaranteed. Indeed, if the pilot is unable to contact the personality of the Walker they often are required to go through their pilot training a second time (which can take multiple years to complete).
Most pilots describe a personality connection like a second set of emotions coursing through their body, urging them towards goals and actions. Some claim to hear whispered words or, very rarely, even a clear voice. Pilots need to learn to understand the personality within the Walker before they can properly work with it. Without the personality, it is little more than a cumbersome machine, but when Pilot and Walker have found their consensus, the machine becomes a tool of destruction and beauty.
Most Walker personalities are more than happy to work together with their pilot, once a connection has been made. Mesa Walkers, on the other hand, are a different story. When the Mesa was first created, it was not considered that the personality would be any different than the others, until the first pilot to attempt a connection with the machine was killed within minutes. The discovery stunned the Maret family and several months of deliberation took place before another pilot was found to try again. More precautions were taken than usual, but ultimately it was impossible to know what had happened. The new pilot, a woman by the name of Eliza Beret von Maret was a veteran Walker user who had been urged by her own Karst walker to attempt a connection with the Mesa.
Eliza sat upon the Mesa's pilot seat for days. Her retainers kept her fed and watered, but she sat silently until, after ten days had passed, her eyes opened and the Mesa came to life. Unlike other Walkers, the personality within the Mesa was immense. A dark sea of emotion and drive, unwilling to bend to even the strongest of will. Eliza discovered that it could be reasoned with, but was unwilling to take a back seat (figuratively speaking). Moreso than other walkers, when a pilot bonds with a Mesa, the bond is unbreakable. Eliza was never quite the same again. The Mesa, unlike the other Walkers, followed her out of the machine. The ocean was behind her eyes from then on, always urging for release. Though she was able to leave the seat, more and more often she refused, and the last years of her life were spent entirely within the pilots seat. When she finally passed, her Mesa refused to move for nearly a decade, rejecting three pilots and killing one before another was finally able to take up the mantle.
New Mesas are still made, and pilots continue to try to connect with them. Despite the risks, the rewards and honour that come with being the one chosen by a Mesa are more than enough to tempt anyone.