The Pokémon TCG: Hidden Fates expansion features the first TAG TEAM trio, and this deck is designed to take advantage of the power of that card. Moltres & Zapdos & Articuno-GX is a powerful card, but it requires a bit of effort to power it up to its full potential. Once you get it there, though, this card can do some major damage to your opponent’s Pokémon.
The first thing to keep in mind is that Moltres & Zapdos & Articuno-GX's attacks require three different types of Energy to use (Fire, Water, and Lightning). Viridian Forest and Energy Spinner both let you search your deck for any type of basic Energy, so they will prove invaluable to get the proper Energy into your hand.
To assist Moltres & Zapdos & Articuno-GX, you’ll want to get Dragonite out as soon as possible. You can then use Dragonite’s Hurricane Charge Ability to help attach Water and Lightning Energy to the TAG TEAM trio. After doing this, you just need a Fire Energy and one other Energy of any type to begin using the trio’s Trinity Burn attack, which hits for an impressive 210 damage.
Of course, once you've powered up to use Trinity Burn, you also have enough Energy for the trio’s Sky Legends-GX attack, which hits three of your opponent’s Pokémon for 110 damage and then shuffles the TAG TEAM into your deck, preventing your opponent from getting a 3-Prize Knock Out.
If you’re going up against a Lightning-type deck, you can use Mewtwo & Mew-GX’s Perfection Ability to copy the attacks of Moltres & Zapdos & Articuno-GX and keep the TAG TEAM trio safe from Lightning-type Pokémon that can hit it for double damage.