Gym Heroes arrived in 2000 as part of the Pokémon TCG's second major expansion era, introducing the beloved Gym Leader characters from the video games. This set marked a significant moment for the hobby, bringing recognizable trainers into the card format alongside their signature Pokémon. Gym Heroes remains a cornerstone set for collectors building complete collections or focusing on the late 90s/early 2000s period when Pokémon cards reached mainstream popularity. Misty's Poliwag represents one of the set's iconic trainer-specific cards, pairing the gym leader with one of her most memorable team members. The artwork captures both character and creature with the charm typical of this era's illustration style. Collectors seek these trainer cards for their connection to the games and anime, making them centerpieces of character-focused collections.