Lana's Popplio is Lana main Pokémon. Ashimari swims at a speed of forty kilometers per hour and its superb swimming speed really shocked Ash when he first saw it swim.
One day, Lana
was out fishing on a Lapras when she saw Skull Gang bulling a Ashimari, She quickly went to save it as it had been deeply hurt and she didn't want it to grow to hate humans so she took it to Nurse Joy (Alola)
to recover and then decided to chose it as her partner.
It participated in the third Alola! Surprise! verses Ash's Pikachu
which was a Pokémon Aquathlon, where the Pokémon compete in both swimming and running. After starting off slow in the running segment and falling behind Pikachu, it quickly made up the difference and quickly passed Pikachu when it got into the water and it won the challenge.