Mars

Rie Shelia Tanaka (codenamed "Mars") is from Majolica Town in the Sinnoh region. She's a former member of Team Galactic and is now a member of the Tekiyoku. She's a Flying Manipulator.

Present
Mars first appeared in Episode 4 with Jupiter and Saturn discussing general Tekiyoku plans with Giovanni. Mars revealed that she and Jupiter would remain in Sinnoh to be stationed with Annie, Oakley, and 4 other members. Saturn said he'll be sent to Hoenn with 6 other members.

Later in Episode 23, Mars was the first enemy for the newly named Mokusetsu in their third region, Sinnoh, as they were in Snowpoint City to find Seirei, the Fairy Plate. She appeared with Argus Steele.

Before a fight started, Jupiter, another former Team Galatic member, made a surprise appearance, avoiding Alain's Vigilant due to the fact that she's a Ghost Manipulator. A fight began for possession of Seirei, with Ash fighting Mars, Alain fighting Jupiter, and Barry, still a non-Manipulator at the time, fighting Argus.

As the fight continued, Mars ran to Alain and used Breath of Fresh Air on him. Alain used the same move right back, but his was stronger, which hit Mars and knocked her out. Jupiter and Argus were eventually defeated after some peculiar events. Mars, Jupiter, and Argus retreated.

Naming

 * Her first name, Rie, is the given name of her Japanese voice actress in the Pokémon anime, Rie Tanaka.
 * Her middle name, Shelia, was randomly selected from an English name generator.
 * Her last name, Tanaka, is another reference to her Japanese voice actress, as this is her surname.
 * Her codename, Mars, is what she's referred to in both the Japanese and English versions of the Pokémon anime. This is her actual name in the anime. Nocturnal Jay decided to have it be a codename. The name simply comes from the planet, Mars. She shares this name scheme with Jupiter and Saturn.

General

 * Her birthday, January 3rd, is yet again another reference to her Japanese voice actress in the Pokémon anime, Rie Tanaka, as this is her birthdate.
 * Mars, Jupiter, and Argus were the first Tekiyoku encounter after Alain named his group the "Mokusetsu".