Alright, so to explain this, Percy is better than Dream and is the same with Techno. Techno would only be able to beat Percy if he had seen his styles multiple times, because Percy changes his style to confuse his opponents. Also, with the fact that Techno is one fourth Greek, I feel as though because of his ancestry, he would learn how to fight like a Greek too. Dream wouldn't understand any of the forms that Percy uses, so it would be hard for him to decipher and fight Percy.
If they were fighting with whatever, Percy would of course win because of his powers, but if he wasn't using his powers, Percy would loose or tie with Techno and win barely against Dream.
Percy's state of "hearing the voices" is the scariest out of the three, Techno and Dream side by side with the second scariest.
Hope this is ok with all of you guys, but with the fanfics that I've read with Mcyt and Percy Jackson, Percy seems to not be very skilled.
Also, Percy had another year added on with constant monsters he had to fight.
Bye!