"They flare their frills and generate energy. A single Heliolisk can generate sufficient electricity to power a skyscraper. It stimulates its muscles with electricity, boosting the strength in its legs and enabling it to run 100 yards in five seconds."
After running around a store, Helioptile got itself stuck on the roof, trying to not fall off the building. Lexi manages to reach it in time, saving it from falling. After giving it some food and calming it down, it ran off from the group back into the town. As Lexi and her friends began to leave the town, Helioptile returns, wanting to join Lexi on her team. She captures it, and when done so it unleashes itself from her Pokéball and pouched itself in her bag, suggesting it wanted to remain outside of it's Pokéball. The Helioptile then joined Lexi as she headed into Santalune Forest with her friends.
Following its evolution, Heliolisk voluntarily decided to remain inside it's Pokéball instead of being by Lexi's side.
Heliolisk appeared many times following this, mainly during Lexi's battles against Team Flare, along with appearing during Lexi's battle against Calem in Victory Road.
Heliolisk's final battles with Lexi were against Siebold during her Elite Four battle and again against Champion Diantha.
Heliolisk made his final appearance during the events of M06, before being sent to the Kalos Daycare where he remains.
Heliolisk can flare his frills to generate electricity. He alone is able to sufficiently generate electricity to power a skyscraper. He's able to run 100 yards in five seconds due to thhe electricity stimulated by electricity.