(Leo user)

When Jason Grace was young, he was taken from the planet of the First Ones by the Horde and was raised by the leader of the Horde, Gaea. He was also raised with someone else, Leo Valdez, his friend, his best friend, his... teammate. Gaea always liked the calm, strong, obedient Jason more than the loud, impulsive, and easy-to-anger Leo, but that never stopped the two from being friends. Until it did.

One day, while out on a mission with Leo, when they both just turned sixteen, Jason and Leo encountered Piper and Percy, who were out looking for Horde ambushes. A fight ensued, and they got separated. Jason, Piper, and Percy rolled down a cliff while Leo was left up, unaware of what was about to happen. More fighting happened at the bottom of the cliff, and then the three spotted the long-lost Sword of Protection stuck in the ground. More fighting, then Jason managed to get a hold of it. It lashed really bright, then Jason had a sort of flashback to someone called Light Hope, and when he regains consciousness, he's like, eight feet tall, in a cool battle outfit, non-greasy hair, and a crown of some sort on his head.

Piper and Percy freak out, taking Jason to Bright Moon, where they figure out that Jason is the first Jupiter in a thousand years. Crazyyyy. Jason pledges to serve and protect, no longer an officer for the Horde and now an official prince. Jupiter, the Prince of Power.

Leo... didn't take it too well, finding out about all this during a Horde attack and having to fight with Jason. Heartbroken and betrayed that his one and only friend left him for some dumb princes, he vowed to serve Gaea and the Horde with his life, whether that meant fighting his ex-best friend or not. After all, without Jason in the picture, he can finally have his chance to shine; that's a good thing… Right?

—

Jason was just training with his friends, the Prince Alliance, consisting of Frank Zhang, Hazel Levesque, Annabeth Chase, Percy Jackson, Piper McLean, and him, though it was more goofing off than actual practice. Eventually, they get a message: some Horde soldiers have been spotted near a village. So naturally, they go check it out. Wrong move. It was a trick andan ambush, and now all of them are trapped by some mysterious people that are not the Horde.

After a long, bumpy ride where they get knocked unconscious, they end up in some arena, and around them are a mix of monsters, Horde soldiers, and random bad guys. Turns out this whole thing was an entertainment setup by the Scorpion Kingdom, now rebranded to the Outlands after a Horde invasion. What're they fighting against? Just giant, practically indestructible robots, big mutant monsters, giant sand worm things, Scorpion guards, and trained fighters that were sent down there due to their crimes as punishment.

It wasn't that great. Jason couldn't even activate his dumb sword without these shock collars put on the group while they were unconscious, shocking them, so no powers for anyone. Percy and Frank were having an especially hard time, due to the warm climate and lack of water; it was not looking good. And to make matters worse, Jason spotted not only Gaea next to the Outlands royalty, but also Leo, his rival for a few months now, who actively tries to kill him whenever they meet. Double great.