Oh, come now. No need to be so sullen. As they say, “to err is human, to forgive, divine.” And you know how forgiving I can be. When it suits me...Valens to Alfonse
Valens rose up the ranks of the Garlean military before losing the right to lead the XIVth Imperial Legion to Gaius van Baelsar and ended up as an assistant to Nero tol Scaeva, who was considered a more gifted engineer than Valens himself. Following Gaius's assumed death, Valens gained the opportunity to lead the VIIth Imperial Legion and Varis zos Galvus commissioned him to create the Weapons. Valens used the orphans Gaius had taken under his wing as disposable test subjects to perfect the Diamond Weapon, using the data from the other Weapons built after it. Following Emperor Varis's death, some noted Valens's greed for power has only grown as he intends to take over the wartorn Garlemald as emperor.
The Eorzean Alliance learns of Valens's actions when the VIIth Legion deploys the Ruby Weapon, which hosts data on Nael van Darnus, at the cost of one of the orphaned soldiers. Gaius joins the search for the remaining Weapons, and with the Garlond Ironworks' assistance, the Warrior of Light tracks down and destroys the Sapphire Weapon off the coast of Terncliff in Ilsabard. This was a distraction so that the remaining Weapons could be transferred elsewhere. Valens orders the orphan ward Alfonse to prepare his fellow orphan, Allie, to pilot the Diamond Weapon as it is near completion.
Following the defeat of the Emerald Weapon at Castrum Marinum, an Echo flashback reveals that Alfonse and his fellow orphaned ward, Rex, deliberately left Allie behind at the Castrum to be discovered by the Eorzean Alliance. Alfonse is using the Diamond Weapon to liberate Werlyt and put an end to Valens's work. Valens, unaware of this, tortures Alfonse for losing Allie by coercing several young children under his own ward to "burn out the bad" from Alfonse with their torches. Having previously intended to use Allie as the pilot for the Diamond Weapon, Valens gives the position to Alfonse along with the threat of mass genocide should he escape or refuse to kill Gaius.
Valens oversees the Diamond Weapon's Oversoul experiment on an Imperial test subject, whom Valens duped into thinking he would spare his family for his participation. The test subject is transformed using Valens's Oversoul technology into a copy of Zenos yae Galvus, but Valens terminates the experiment as he deems Zenos unable to be controlled. He proceeds with the next round of experiments with the deceased subject's family, eventually wanting to merge Alfonse into the core. Valens greets Allie when she returns to Werlyt and assigns her to pilot the Diamond Weapon after she presented him with the Weapons data the resistance amassed. Valens knows she intends to use it against him and has the Diamond Weapon shutdown and orders his men to drag Allie out of the cockpit to personally torture her to death. Allie unintentionally activates the Diamond Weapon's Overmind, allowing Alfonse to protect her while destroying the VIIth Legion headquarters.
After the Warrior of Light subdues the Weapon and takes Allie away, Valens reveals himself to Gaius and reveals Alfonse's fate before the two settle things in a duel. Despite having the advantage with Gaius's combat data, he fails to counter Gaius's Terminus Est Corcea Mors, having had no record of such an attack. Alphonse's mind reactivates Diamond Weapon to grab the injured Valens, who pleads for his life before the visions of his numerous victims as he is crushed to death with his corpse tossed away.
Valens van Varro has fair skin, green eyes, brown hair, and the third eye typical to pure-blooded Garleans. As a Legatus to one of the Garlean legions, Valens wears a purple suit of armor similar to Regula van Hydrus.
Valens is among the most ruthless and sadistic Garleans in his disdain towards the other races, believing his people superior and all others to be savages. This prejudice manifests in his methods of abuse and the torture of his subordinates, both physically and psychologically, along with seeing those of non-Garlean birth as disposable test subjects. Valens doesn't even bother to properly remember the names of those under his command. His sadism borders into mania in how he treats his subordinates, almost acting giddy when "punishing" them. Valens has no qualms about going back on promises, especially when they are with those not of Garlean blood. Even some of those in the Empire's service find his cruelty unnerving.
Like most Garlean officers, Valens responds poorly to setbacks and bad news, lashing out on his subordinates. He regularly beats his wards, such as Allie and Alfonse, to vent such frustrations. Nonetheless, Valens remains determined to accomplish his goals, ready to sacrifice whatever he must for them. Valens is power-hungry, willing to experiment on others and create his own Ultima Weapons to claim the Empire for himself.
Valens's hatred for Gaius Baelsar is his prime motivation in creating the Weapons. He resents and envies Gaius, not only for his skill and leadership, but is bitter about Gaius becoming the Legatus of the XIVth Imperial Legion over him. Out of spite, Valens opposes everything Gaius stands for, including respecting those who serve the Empire based on merit and loyalty, rather than on race or origin. As such, he is adamant in his belief that pure-blooded Garleans are superior to all others.
Though he deludes himself by claiming he surpasses everyone else, Valens's main flaws are his twisted arrogance and over-reliance on his collected data. When he throws his subordinates at the enemy so he can escape, Gaius calls him cowardly, and at Valens's last moments proclaims him beyond salvation. As he begs for his life, Valens still believes himself superior to Gaius and everyone else.
Unlike most high-ranking Garleans, Valens's appearances are not accompanied by "Imperial Will"; instead, "Tears for Mor Dhona" plays during cutscenes featuring him.