|“||I can still fight with the other hand.||”|
–Pollux after being injured, in The Last Olympian
Pollux and Castor are both seventeen when Pollux sees his twin brother, Castor, die in battle. At Castor's funeral, Pollux tries to speak for his brother, but is unable to choke out the words due to his colossal grief. He then lights the funeral pyre and sits back down mournfully, trying not to cry. Dionysus is seen following him out to make sure he is all right.
Pollux is the only member of his cabin. He fights bravely in battle and calms the other demigods down when they are worried and anxious about the spy among them. He is shown to be a good warrior known to have common sense.
He breaks his arm in battle, and Percy Jackson insists he not get back into battle, but doesn't tell him why. He tells Pollux it's a "personal favor." Dionysus specifically requested that Percy keep his son safe, in a vision Percy had, but Percy didn't want to embarrass him by revealing it. This possibly implicates that Dionysus had been watching over his son after the death of Castor, and perhaps Pollux hadn't dealt with Castor's death well.
Pollux is level-headed and a good warrior. He is not very close to Percy Jackson, Annabeth Chase, or Grover Underwood, but is very brave and protective of his brother, who is his best friend. When he breaks his arm, he was willing to fight with his left hand, though he only practiced with his right, which would have likely been suicide had he gone back in battle.
In The Lightning Thief, Pollux is seen very briefly with his brother and they are both described as "a couple of plump blond boys who looked just like Mr. D."  As a result, it can be said that he is not athletically built, much like his brother Castor.  In addition, Pollux is not described as being very good-looking, with slightly curly blond hair, violet-colored eyes.
- ADHD: Like most demigods, he possesses inborn supernatural battle reflexes and senses that he uses to analyze the fighting style of his opponent.
- Dyslexia: His brain is hardwired for Ancient Greek.
- Chlorokinesis: As a son of Dionysus, he can control plants, grape and strawberry vines. He's seen with his brother, Castor, making the strawberry plants grow.
- He can presumably control madness, being able to cure or cause it.
- this is unlikely, as he could not care for Chris.
It is shown that they were very close and that they loved each other very much. Pollux was brokenhearted at his brother's death, and this helped his fury against Kronos and his monsters, so he had no doubts about him fighting for his brother's memory. He was also prepared to do a suicidal charge into battle against the Titans to honor his brother's memory and avenge him.
Dionysus is very protective of Pollux as shown in The Last Olympian when he asks Percy to keep him safe from harm's way. This is because he was very scared and still upset over Castor's death in The Battle of the Labyrinth. It is unclear if he and his brother had interacted with their father much while they were at Camp Half-Blood together.
- Pollux is actually the Latin version of Polydeuces, which means 'much sweeter wine', a suitable name for him as he is a son of Dionysus, the god of wine.
- He and his brother are named after the Gemini, Castor and Pollux.
- Like in most versions of the story of the Gemini, Castor dies, but unlike those stories, there are no known attempts to either restore him to life or reunite them.
- In the solar system, both Pollux and Castor are stars and both in the constellation Gemini, the twins.
- In ancient Rome, Castor and Pollux had one of the greatest temples, located right in the center of the city.
- In the Latin Culture, Pollux and Castor are known as the Gemini or Castores.
- The name Pollux means "Crown".
- Pollux and Castor were named a pair of twins in Greek mythology, in which Pollux was a demigod son of Zeus and Castor was mortal son of Tyndareus, a king of Sparta. They were the brothers of Helen of Troy.
- Pollux and Castor are the names of two brothers in The Hunger Games trilogy as well, and incidentally, Castor was killed while Pollux survived.