Hogwarts vs Camp Half-Blood and Camp Jupiter

If it takes place at Hogwarts, Percy could just destroy it (Hogwarts is right by a lot of water) plus Hazel could also be in that list. But CHB and CJ have much better combat than Hogwarts and could easily win in close combat. Also Piper could just tell some to fight each other and win easy. And if you count Dionysus, they could win easy.

Also i would say Leo Valdez could fight against many of Hogwarts students. Some demigods are just too strong. I would say CHB and CJ would win.

Hogwarts is not just a castle, it is protected by magical enchantments that were never broken except when Voldemort attacked with the full force of the deatheaters, giants, trolls, dementors, snatchers and other wizards loyal to him. Even then it took hours to get inside the castle and this was post-Dumbledore's death so the castle would be lesss defended than before. It does not matter how much water Percy throws at it, it is still just water and will not penetrate the castle grounds. Also the water surrounding Hogwarts is freshwater not saltwater so Percy would have less power over it. Even he could control the water and damage Hogwarts the force would probably kill him or at least put him out of action for the fight. Leo could fight against some wizards but he is not a fighter primarily and a teacher at hogwarts or senior student could easily beat him. Leo is also the only known demigod who is alive and able to control fire. Hazel is powerful but I don't think her magic measures up to Harry Potter's level and is nowhere near someone like Dumbledore. Close quarters is meaningless as fights will be over before they can get close without the element of surprise and older students can teleport away. The majority of demigods have no powerful abilities. The only kids at Camp Half blood who were mentioned to have special abilities were Drew, Piper, Leo, kid of Ares in extreme circumstances (blessing of Ares control over defeated soldiers), kids of Demeter, Poseidon, Hades, Zeus and Hectate (I might have missed some out). This would be less than half the camp and the number would be even lower at Camp Jupiter as many demigods were distant descendants and didn't inherit any powers. The seven demigods in the prophecy + Nico and Thalia are exceptionally powerful and most demigods wouldn't stand a chance against a competent Hogwarts student even without the numbers advantage. Also Hogwarts outnumbers camp Jupiter and Camp Halfblood combined four to one. I like the Heroes of Olympus characters but it isn't even a close battle.