Hi there. In this Pokemon TCG post I cover a powerful combination that features Wellspring Mask Ogerpon ex and Double Turbo Energy.
Wellspring Mask Ogerpon ex
Wellspring Mask Ogerpon ex is a Water Tera Pokemon that is also a Basic Pokemon ex. It has 210 HP with one retreat cost. The first attack does 20 damage for one colourless energy plus not letting the opponent's Defending Pokemon retreat in the next turn.
The second attack of Torrential Pump does 100 damage to the Active opponent's Pokemon. You have the option of shuffling 3 Energy attached to this Pokemon into your deck in order to do another 120 damage to 1 of your opponent's Benched Pokemon.
The Powerful Combo
This combination use three cards.
The addition of the Sparkling Crystal ACE SPEC card really puts the Double Turbo Energy and Wellspring Mask Ogerpon ex combination into the limelight. By attaching Sparkling Crystal to Wellspring Ogerpon ex the second attack costs one Basic Water Energy less in order to use the Torrential Pump attack. It costs less to do 80 to the Active Pokemon (100 minus 20 from Double Turbo) plus 120 to a Benched Pokemon. In theory and in practice you can get a double attack if you go second on your first turn.
I am not sure how often you would get all three cards to pull off this type of combo. You need a Tool search card like Arven or Town Store Stadium for the Sparkling Crystal, a Nest Ball for the Wellspring Mask Ogerpon ex and a way to get the Double Turbo Energy. The Supporter card Colress's Tenacity from Shrouded Fable would be a powerful card in searching for a Stadium Card like Town Store and any Energy Card. Use it to get Double Turbo Energy and Town Store stadium. The Town Store Stadium would be used to get the ACE SPEC tool card if it is not prized.
A hard counter to this combination would be Manaphy. Manaphy prevents damage from attacks onto your Benched Pokemon.
Stadium cards like Jamming Tower negates the effects of Tool cards and Temple of Sinnoh negates the effects of Special Energy cards and turns into to just a single Colourless (*) Energy. Both are good choices but Jamming Tower seems to be more powerful as a lot of popular decks run tool cards more so than Special Energy cards.
Ruling With This Combo
The motivation behind this post is based on this useful Youtube video from start to 7:49. It has useful card rulings and clarifications with combinations.
If the Wellspring Mask Ogerpon ex second attack is used with Double Turbo Energy, the attacking player has the option to shuffle 3 Energy from it to the deck. When you have the ACE SPEC card Sparkling Crystal to the Water Ogerpon ex you can attack with just Double Turbo Energy. In this case to do the extra 120 damage to 1 of your opponent's Benched Pokemon you can just shuffle the only Double Turbo Energy card from Wellspring Mask Ogerpon ex to your deck.
The card's attack cost does require one Water Energy and two colourless Energy. But if you have the ACE SPEC tool which allows for just 2 Colourless Energy in its attack cost the attack still happens with the optional attack one Benched Pokemon for 100 damage (120 minus 20 from Double Turbo I think).