Rayquaza is, I believe, a dragon-type. Try using ice-based attacks.
Ghost & Flying. I believe that's it! Not dark or bug because although they're super-effective against Psychic, they are not-effective against Fighting. And not Psychic, because though it's super-effective against Fighting, it's not-effective against Psychic.
Water and Grass attacks are super effective against Onix.
psychic pokemons and attacks are super effective
super effective is bug
Rock, electric, ice, and psychic types are super effective against Crobat.
icebeam is super effective
Deoxys is better since it can learn ice beam which is double super effective against flying/dragon type pokemon. rayquaza is better becuz deoxys dies easly and its states r low and besides rayquaza can use crunch
Flying and Psychic are super effective against fighting
Lightning is super effective against water. I hope this helps.
Ghost & Flying. I believe that's it! Not dark or bug because although they're super-effective against Psychic, they are not-effective against Fighting. And not Psychic, because though it's super-effective against Fighting, it's not-effective against Psychic.
Water and Grass attacks are super effective against Onix.
super effective is bug
psychic pokemons and attacks are super effective
Bug Type and Fighting Type moves are super effective against it.
Steel is super effective against rock type pokemon.
Rock, electric, ice, and psychic types are super effective against Crobat.
normal type Pokemon are not super effective against any type.