Starmie ex is one of the best decks in Pokémon TCG Pocket thanks to its simple setup and abundance of support cards. You can play the deck in different ways depending on your play style.
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While most players will choose the Articuno ex variant of the deck, there are also several alternatives that you can play with the same core, such as Greninja, which is excellent in certain situations. As one of the best decks to take over the game so far, it can be difficult to know which variant to play or which to invest your hard-earned Pack Points in. Here is some guidance.
The Articuno ex variant is probably the strongest and most consistent version for the Starmie ex deck. It combines Starmie ex's easy damage output of two Water Energy for 90 base damage with the ability to use Starmie ex's zero retreat cost to call in the Articuno if it starts to take too much damage.
It's a pretty easy deck to understand, just stock up and deal damage while using Misty to potentially get all the Water energy you need with a few good coin tosses.