She started out as a Flaaffy in TPI: Human Fun. She showed that she is not nice, like in episode 3, where she somehow got Magmar out. In Episode 5, Samurott and the rest of her team tried to stop here from being safe in the challenge, but she got Simipour out in the end. In episode 6, Karma came when the Charizard from Tellyzx's PLVS burned her. In episode 7, she made a bomb fort with a button to start it. How she survived is unknown. In episode 10, she got revenge on Cofagrigus by blowing up his surfboard and then eliminating him. In episode 13, she started dating Croconaw right when he was eliminated. She was finally eliminated in episode 16 at the final 3.
Mareep appears in Nickinor2's TPI. Here she serves as the main antagonist until her elimination. She makes an an alliance with Misdreavus and Murkrow and forces them to hypnotize other contestants. She is eliminated in episode 21 after evolving into Flaaffy.