Excluding Arceus holding a Mind Plate, the best Psychic-types by base stats are Mewtwo and Lugia.
Excluding legendaries, the best Psychic-type by base stats is Metagross.
Dark-type moves
He uses fighting type Pokemon so its better to use pyschic, flying type Pokemon
you can use a flying type pokemon like starly or a pyschic pokemon but watch out her lucardio
Try using a Bug type or a Dark type pokemon. Either use Foretress, Scisor, Umbreon, or Sneasel.
The Petalburge Gym uses Normal Type Pokemon so you should take pyschic Pokemon or fighting type Pokemon if you want to beat them quickly.
Dark, bug, and ghost.
sorry no
Yes, Pyschic is TM29 in Pokemon.
use Dark type attacks like "Bite". It's really simple since's it's a Pyschic Pokemon
He dose eventually
Abra, Kadabra, Alakazam. Mr.Mime. I think Venomoth but i dont think so.... PS subscribe to MajestiikPokemon on youtube please it will help :D
potentially, yes. For instance, Gyarados can learn Dark Pulse (Dark moves are super effective on psychic Pokemon) and Gyarados is a Water type. Also, neither Pokemon will really be super effective on the other (if they only have water and psychic moves, respectively, and are not of two types), so the stronger, better trained Pokemon will probably win, or they will each have an equal chance.