Percy. It's stated by Nico that Percy is the most powerful demigod he's ever seen. This is saying a lot because Nico is really powerful himself seeing as he survived Tartarus alone. Although Jason is the son of Jupiter and can also fly, he hasn't really done as much as Percy has.
In terms of power Percy solos in every aspect. Cause among all the demigod Percy and Nico powers all reflect their fathers abilities while others are limited to all strength the difference between them is that they both get tired that's why they could easily die.
Jason can also generate blasts of wind powerful enough to topple Giants. As a son of Jupiter, the most chiefest of the Big Three, Jason is most likely one of the most powerful demigods of all time, but his sword skills are the most prominent method of combat than his supernatural powers.
The second tallest is Jason Grace, at 6'0. He was mentioned to be around an inch or so above Percy, but he's a growing kid, and was born July 1, 1994. Third runner up is Percy Jackson, at 5'10/2.
Jason and Percy have both been established to be the exact same age in the series, with Jason having trained much longer in Camp Jupiter (12 years) than Percy had at Camp Half Blood (5 years).
Well Piper was so distraught that she tried to charmspeak herself into thinking he was still alive and was furious at Lester. Leo was pretty upset about it. And Thalia was angry at Lester for a bit.
Wiz: Percy Jackson, son of Poseidon. Boomstick: And Jason Grace, son of Zeus. Wiz: Granted, these two warriors have fought each other once before, with the intention of killing each other, but the outcome of the fight was ultimately uncertain as it was interrupted before it could properly develop.
Jason Grace is one of the main protagonists of the second Camp Half-Blood series, The Heroes of Olympus. He is the son of Jupiter and Ms. Grace and the younger brother of Thalia Grace. He was a praetor at Camp Jupiter until he gave his rank to Frank Zhang; he is the current counselor of Cabin One at Camp Half-Blood.
Jason Grace: The 16-year-old son of Jupiter who can fly, control winds and lightning, and create storms. He is a natural-born leader and was a praetor before Hera took his memory and sent him to Camp Half-Blood.
Jason Grace is one of the seven demigods of The Great Prophecy in The Heroes of Olympus. He is the son of Zeus's Roman form, Jupiter. In the series, Jupiter is portrayed as a more level-headed and rational version of Zeus, and Jason has these same attributes.
Jason's a founding member of the Heroes of Olympus, along with BFFs Leo Valdez, Frank Zhang, Hazel Levesque, Percy, and Annabeth. To say nothing of Piper McLean, his amazing girlfriend, who fell in love with him even before they technically met.
She can use a bow and is more agile than Percy. Nico himself said, after meeting Jason, that Percy was the most powerful demigod he'd met. That's true, but power, skill, and intelligence all play a key factor in a fight. Thalia's the daughter of the strongest god, and has similar power levels to Percy.
Mortician: In terms Skills and Training, Luke was a way better fighter than Percy, Percy only has about 4-5 years of experience on fighting monsters and Demigods, while Luke has spent many years training from two powerful Jedi and became one of the strongest Jedi.
Jason Grace awakens on a school bus which belongs to the Wilderness School, unable to remember anything about his past. He is next to Piper McLean, his apparent girlfriend, and Leo Valdez, his apparent best friend.
Sometime later, Piper breaks up with Jason due to feeling that their relationship was forced onto them by Hera and her mother, and wanting to live for herself even though later after he dies, Piper states that she still loved him.
Jason Grace: His fatal flaw was his temptation to deliberate. For years in Camp Jupiter, Jason always relied on careful choices, compromises, and hearing both sides of a debate. He never chose what he wanted.
Different environments account for different outcomes. If they were near a pond of some sort, Percy would win easily. In an electrically charged environment, Jason would defeat Percy. There is also the question of how far their abilities can stretch.
Thalia Grace is a fictional supporting character in Rick Riordan's Percy Jackson and the Olympians series, as well as a minor character in the Heroes of Olympus, as Jason's sister. She is the demigod daughter of Zeus and Beryl Grace, a famous mortal actress.
Piper avenges Jason by killing Medea and says to her "I'd tell you to say hello to Jason for me, but he'll be in Elysium. You... won't." Piper appears in the fifth and final book The Tower of Nero where she has settled into her life in Oklahoma with her father.
In terms of swordsmanship, Percy is superior, having bested gods such as Aries and Hyperion. In terms of strength, it's really no contest. Percy held up the earth for a time in instead. when it comes to speed, Nico D'angelo takes it.
Upon returning to Camp Half Blood, Percy is betrayed by his friend Luke, son of Hermes, who turns out to be the human hero whom Kronos used for the theft. Luke poisons Percy, and tells him before leaving that Kronos will rise and destroy the age of the gods. Western Civilization is unraveling.
The two engage in battle but are interrupted by mortals who recognize Percy as the boy from the news. Ares fires at the mortals while Percy uses the waves against him and stabs him in the heel. As Ares prepares to implement his next attack, a strange force stops him and he lowers his sword in defeat.
