Firestorm II (CW)'s powers and abilities
Firestorm Matrix Connection/Meta-Human Physiology
When Jax merges with Martin Stein, the two create the nuclear-powered composite being Firestorm. The F.I.R.E.S.T.O.R.M. Matrix is controlled by two individuals, or "halves"; when they achieve physical contact, the Matrix takes over their biology and merges them into a singular being. When the two halves of Firestorm merge, the Matrix has them take on the form of the individual that has the stronger body. However, after Martin took a serum created by Cisco Ramon and Harry Wells, it severed Jax and Martin's link; therefore he no longer has any connection to the Firestorm Matrix.
Firestorm has so far seen to have at least two methods to achieve flight. The first and most common is when he uses fires nuclear blasts downward at a consistent rate, thereby generating enough force to defy gravity and allow for stable prolusion and gliding. This flight style is his preferred and most practiced choice. The second method is unclear, as he is shown to be able to fly at impressive speeds without the need of his blasts. How he achieved this skill or how he even does it is unclear.
While fighting Nazis in 1944, Jax and Martin discovered that their nuclear powers can manipulate matter at an atomic level and arrange its subatomic structure into a different substance altogether. He first used this by turning a rifle into dust by grabbing it. Using this ability, Firestorm is able to transform a radioactive meteorite into water. Over time, the duo further refined this skill, able to transmute machinery into countless smaller and more complex compounds, such as a shielded safe into a pile of jellybeans.
Firestorm is virtually a living reactor, and as such, creates great amounts of nuclear energy via the innumerous atomic reactions constantly occurring in his body. That and his mental capacity to process both fission and fusion, allow him to harness the energy emitting from his either his own body or any near source of energy that’s near.
Firestorm has shown the ability to not only generate nuclear power but also contain the energy coming from outside sources by absorbing its output. He did so when he absorbed the blast from Vandal Savage's nuclear warhead. He's also able to manipulate and absorb the flow of other forms of energy, as shown when he was able to siphon off energy from the Pentagon.
Jax can hear Martin's disembodied voice while the two of them are merged into Firestorm. Even when they are separated, their link allows them limited communication of sensations or emotions.
Due to the nuclear nature of the transmutation of the two bodies, Firestorm is able to release nuclear energy from parts of his body in the form of fire. He can use his control over the energy to project it willingly in the form of concussive blasts. These "nuclear blasts" are often shown to be quite powerful and have shown to be able to range from being able to knock unarmed humans out unconscious to being hot enough to burn through solid structures and even causing extreme harm to meta-humans. The impact of these blasts can sometimes create an explosive-like force.
While in his Firestorm form, Jax has performed feats of strength that surpass those of normal humans. He was able to rip apart straps made of Tiberian steel, which were able to encase both Hawkman and Hawkgirl.
Whilst he lacks a college degree, Jax is highly intelligent, having quickly learned how to operate and perform maintenance on the future technology of the Waverider. He is also shown to be a talented actor, able to perform an accurate British accent.
To help his mother with bills, Jax gained a job in a car repair. To which, his skill at have prevented very adaptive, able to apply it to the various needs of the Waverider and technology encountered on their travels. He eventually was appointed by Rip to be chief engineer for the Waverider (though Mick Rory regularly reminds him that he's the only engineer on board). Jax's intellect from his time traveling adventures has risen to a point where he finds himself bored with 21st century engineering.
Expert Hand-to-Hand Combatant
While unknown to what degree, Jax has shown some skill at hand-to-hand combat, being able to fight off and even tackle a member of Vandal Savage's cult while the Legends attempted to reclaim Carter Hall's body. This is probably due to his past experience as a quarterback. He is also shown to have a very effective punch, able to knock out a League of Assassins member with a single strike and hold off a 12th century knight wielding a sword with a bow.Jax was even later able to disarm and knock out Malcolm Merlyn after stabbing him with an arrow.
Jax is gifted with great natural talent in athletics. During his time in high school, he was a star quarterback who earned a full scholarship to any college/university of his choosing. However, after the particle accelerator explosion, his leg was too damaged to ever play football again, costing him his scholarship.
In the Old West, Jax used a revolver to shoot a gun out of a man's hand while on a horse. He also wielded a bow in the 12th century and fired two arrows in the chests of two knights on horses.