The initial Pokémon TCG Pocket meta was quickly dominated by a few powerful decks, most notably those centered around Misty and water-type Pokémon. The frustrating aspect of Misty decks stemmed from their reliance on coin flips, leading to wildly unpredictable outcomes. A lucky streak could result in an overwhelming early game advantage, while an unlucky one could leave the Misty deck significantly weakened.

Three expansions later, instead of seeing Misty decks countered or replaced, the latest expansion, Triumphant Light, introduced a card that further amplified their power: the Irida Supporter card. This has understandably frustrated many players.

While Misty decks aren't necessarily the most powerful, the inherent luck element makes losing to them particularly disheartening. Misty allows players to flip coins repeatedly, attaching a water-type energy to a chosen Pokémon for each heads. This could result in nothing, or a massive energy boost, creating a highly variable gameplay experience. A lucky Misty can lead to turn-one victories, while more commonly, it allows for the rapid deployment of powerful cards before opponents can establish a defense.

Previous expansions exacerbated the problem. Mythical Island introduced Vaporeon, enabling easy energy manipulation between water-type Pokémon. Space-Time Smackdown added Manaphy, providing even more water energy. Both expansions also introduced powerful water-type Pokémon like Palkia ex and Gyarados ex, solidifying water decks' dominance.

Triumphant Light's Irida card further strengthens Misty decks. Irida heals 40 damage from each Pokémon with attached water energy. This allows for significant comebacks, especially when combined with the energy generation potential of Misty, Manaphy, and Vaporeon. Previously, grass-type decks were the healing specialists, but Irida shifts this advantage to water decks.

Some TCG experts suggest DeNA, the developer, introduced Irida to counter Misty's dominance, forcing players to make difficult deck-building choices. With only 20 cards allowed per deck, including Irida means excluding other cards. However, many players have found ways to effectively utilize both Irida and Misty in their decks.

The upcoming Pokémon TCG Pocket event, offering rewards for win streaks, will likely see a surge in water decks. The event’s difficulty is amplified by the potential for swift defeats at the hands of lucky Misty decks, even with Irida providing backup. The prevalence of these decks suggests considering using a water deck yourself for this event, to improve your chances of winning.