As one of the most powerful Trainers in the Pokémon universe, Cynthia's team is nearly as important as she herself is. Each of her partners have been with her for a long, long time and they are each incredibly powerful, even by their own species' standards. For anyone familiar with Pokémon game mechanics, ALL of hers have perfect IVs--meaning they're the strongest possible of their species.
ALL of the Pokémon she possesses--particularly those comprising her main team--are very rare and very, very difficult to raise, each one being a testament to her skill, compassion, and knowledge.
GARCHOMP
Cynthia's signature Pokémon she has had since a child. It is a dragon and unarguably her strongest partner. It is fiercely loyal to her, but has a habit of collecting shiny things.
It is capable of swimming through land, through water, and flying at supersonic speeds. Its skin is rough like a shark's.
It uses the earth, blade-like fins, and fire to battle; its strongest attack is Draco Meteor, in which it summons literal meteors to strike the battlefield.
LUCARIO
A serious and serene Pokémon that somehow puts up with its master's clumsy and naive behavior. It is very loyal and hard-working: it trains itself even when Cynthia gives no command to.
It possesses the power to read 'auras', energies given off by all beings; it uses this as form of empathy, sense all beings up to a mile away, and to see without its eyes.
It fights by using its own aura as well as various martial arts.
SPIRITOMB
It is the 'Forbidden Pokémon', being composed of 108 sinful souls sealed within a mystical keystone over 500 years ago. These souls were awakened--but still confined to the Odd Keystone--during one of Cynthia's archeological finds.
It is devious, cruel, and enjoys causing mischief. In battle, it uses various abilities derived from its undead powers to confuse, curse, and hypnotize opponents.
It possesses no sense of kindness or empathy, but nevertheless is under Cynthia's complete control.
EELEKTROSS
MILOTIC
A Pokémon famous for its compassion and ability to sooth angry, violent, and sad individuals; it is able to help prevent conflicts and calm restless spirits.
Being evolved from an ugly, weak fish that Cynthia nevertheless loved and cared for, it holds tremendous love for its master. Despite its beauty, it still holds insecurities from its younger life, just like its master.
It battles using water, ice, and many mystical defensive powers.
BRAVIARY
Gastrodon
Togekiss
Roserade