First and foremost, Ben excels at combat. He boasts an immense pool of aetheric potential, but is completely ignorant in how to wield it beyond mere instinct. Trained in all the tools of war, be it the lance, the greatsword, or the bow, he has even learned more recent weapons such as the Pistols manufactured in Ishgard. Having spent two decades on various battlefields, he is adept at warfare tactics, strategy, and combat. His armor is like a second skin to him, and his weapons an extension of his body. He never seemed to take to the Arcane Arts, the complex hand gestures and incantations difficult to memorize just right.
Not a complete fool, what he lacks in arcane ability he makes up for in being proficient at puzzles and solving riddles. His knowledge of magic is mostly metaphorical and he understands the base concepts but not the nuance or the ability to manipulate his aether in such a fashion.
Due to his traumatic childhood, that burden has manifested in a dark side that both torments him and empowers him. His large pool of aetheric energy manifests itself in enhancing his physical capabilities making him stronge,r faster, and more dexterous than the common footsoldier. Learning how to control that darker side of him is one of his goals and learning to truly tap into his potential as a warrior. His darkside manifested vaguely and in dire situations with little control or guidance until a comrade, Jin, started to tutor him in the finer arts of a Dark Knight. Since then, his darkside has manifested into a reflection of himself, taunting and tormenting him in a way only he can witness, but in exchange he has grown in his power and learning to accept that aspect of himself is an inevitability, the alternative being consumed by it. When he is in 'control' of his power, an aura of red aether manifests around himself. Yet when his aura turns black, his darker self holds the reins and while he is extremely powerful he cannot tell the difference between friend and foe.
Blessed with the Echo, the Crystals blessing has manifested with Ben being able to understand all dialects; providing him with a sixth sense in battle that causes his body to react before his brain has caught up; and in dire situations of life or death, tap into the blessing of the Crystal that enhances his physical capabilities beyond what he is normally capable of.
Mentally, Ben's strenghts are in his ability to read between the lines and piece together details others may overlook. He can read people easily, determining their good or ill will due to their mannerisms or speech. When presented with a puzzle or ancient inscription, he can piece together the symbols somehow to make sense of it through his keen intuition. He has little patience for diplomacy, preferring to get straight to the point and ignore 'niceties' or just fight about it and whoever is still standing is deemed right. On the other hand, he has the patience to talk people down when they are emotional and he recognizes that their pain is genuine and not an act.
Despite Ben's potent aetheric potential, he is utterly inept at thaumaturgy or conjury. Decades on the battlefield and little "proper" learning beyond the basics one would learn by the age of 12, he just hasn't put in the time that the arcane requires to master their abilities. He understands the boon that magic can provide on the battlfield, but he accepts that he just isn't proficient or patient enough at the Arcane to wield it himself. Beyond the basics most things Magic are considered "hocus pocus" to him that's beyond his understanding.
Ben's intense hatred and determination to destroy anything Garlean sometimes results in reckless endeavors that put those close to him in danger. His tunnel vision on the subject and utter dismissal of any notion that there may be innocents within the Empire itself causes disagreements and comes off as offputting to more charitable souls. On the battlefield his confidence is sometimes so great that he seems utterly convinced that nothing can harm him, so when harm does eventually befall him he finds himself licking his wounds for an extended period of time. His recklessness ends up saving others in the long run, but at great personal risk to his own health more often than not.
When he is convinced he is right, and the other person is wrong, he will fight tooth and nail to get them to agree with him or get out of his way which ends up with him butting heads with figures of authority or some employers. Even when he is right, his utter lack of polite language or consideration for the other person's viewpoint makes it difficult for him to sway some people to his way of thinking. Chains of command are utterly meaningless to him, he works for someone because he wants to, not out of any obligation or respect for authority.
Ben's brazen nature often masks the kinder and more sensitive side of himself to the point where even his close friends view him as an arrogant man with a thick skull more often than not. Only in the presence of children, the elderly, or animals does this side shine through. He also has a tendency to wander off on his own and spend time alone, taking time to unwind in his own way without notifying anyone that he has even left. He is often oblivious to the emotional state of other people, being purely focused on his own mindset and how he operates. Despite how well he can read others, he is usually focused on their strengths or exploitable weaknesses, and not their mental well being or emotional health. His traumatic childhood has made him a believer that relationships are fluid and temporary, and those moments are to be cherished but not mourned when they end. This makes him appear cold and distant to others, but makes him never feel lonely, even when alone. And as such, it weakens his empathy for others that require human contact or emotional intimacy due to his tendency to operate mostly on his own. He struggles with getting along with others or opening up to them, considering his battles his own and only accepting aid when it's thrown in his lap.
When in battle, he fights with his sixth sense and basic combat ability until he's pushed to tap into his darkside. With an aura of red aether he becomes stronger, faster, and more dexterous with his weapons to give him the edge. When pushed to the brink his aura will either turn blue or black, the former being when the echo takes hold and gives him just that extra bit of strength to see the fight to the end, while when black it is almost a living death. His body broken and his mind gone into a berserker rage where he pushes himself beyond the limitations the mind puts on the body to prevent it from destroying itself. This state often leaves him broken and in need of healing and rest for an extended period of time.
Stealth is another aspect he is adept at, good at sneaking and disposing of enemies quietly with a knife. At range he is adept at the bow or the pistol, his lack of depth perception being a hindrance he's learned to work around over the years.