Machamp

Decklist from Kanten.

Overview

This deck's main attacker is Machamp, a Stage 2 with 120 HP and two good attacks. Derail costs {F}{C} for 40 damage and discards a Special Energy card attached to the Defending Pokémon. Swift Blow costs {F}{C}{C} for 60 damage, plus 20 more for each React Energy attached to Machamp.

The cards that you use to set up Machamp are pretty standard. You have the Holon Engine, Jirachi + Pidgeot, and Electrode ex + Pow. (It's actually rather rare to see both Pidgeot and Electrode ex in the same deck; most decks play one or the other, or none at all, so Machamp is quite fortunate to be able to make use of both of them.) Windstorm removes Cessation Crystal and re-enables all your setup Pokémon. There is a 1-of Solid Rage if you need a bit more damage to turn a 2HKO into a 1HKO, or to punch through Resistance.

Ideal Gameplan

Holon Mentor for Machop, Jirachi, and Pidgey, whichever you're missing, then attach an Energy to your starter and retreat to Jirachi. Use Wishing Star to dig for Rare Candy and Pidgeot. Evolve Pidgey into Pidgeot, then use Quick Search to build Machamp with manual Energy attachments. Throw that Machamp at your opponent while you build a second Machamp and Voltorb on your Bench. Once the first Machamp falls, evolve Voltorb to Electrode ex, Extra Energy Bomb the Energy from the KOed Machamp onto the new Machamp, and continue attacking until victory is yours.

Unique Points

You can boost Machamp's damage output by attaching more React Energy to it, even if it already has the minimum {F}{C}{C} required for Swift Blow.

Since this deck plays Heal Energy, remember you can use Jirachi's Wishing Star, attach Heal Energy to wake it up, then retreat. The Heal Energy can be gotten back later with Electrode ex's Extra Energy Bomb, but note that the healing effect will not occur, since it was attached from the discard pile instead of the hand.

Rainbow Energy allows Jirachi and Electrode ex to attack. To be honest this hasn't come up in any of the games I've played, and it may be a holdover from when the deck ran Mew δ, so it should be fine to swap it for another Fighting Energy. 

You have barely enough Prizes to Extra Energy Bomb twice (you give up 4 for two Electrode ex and 1 for Machamp), but most of the time this will not be an option since Jirachi gets sacrificed and would become the 6th Prize. The second Voltorb and Electrode ex can be safely used as discard fodder.

A tip against Bombtar that's using Holon Energy FF to remove its Fighting Weakness: you can Pow Energy away to expose its Weakness again.

Tweaks

Mew δ and more Rainbow Energy (over Fighting Energy): Counters Sceptile ex.

Mr. Briney's Compassion: Can be used to deny KOs on Machamp and reuse resources attached to it. It can also be used to pick up Jirachi so it doesn't become Pow fodder.

Strengths

This deck is unaffected by Desert Ruins and Crystal Beach (the latter of which can't be said for Bombtar). Nor do you need to play those Stadiums yourself: Derail deals with Special Energy cards much like Crystal Beach would, and Desert Ruins is unnecessary with Machamp's high damage output. This frees up deck space, allowing you to confidently play 4 Windstorms — most of the time Windstorm will be for Cessation Crystal, but if you encounter the odd Battle Frontier, or if Cursed Stone's damage is piling up, you won't be left without an answer.

Derail is good at punishing decks that play lots of Special Energy cards, or rely on Holon's Castform for Energy requirements. Out of the decks that don't play Special Energy cards, a large portion of them are Stantler decks, which Derail 1HKOs anyway due to Weakness.

This deck is really good at beating up Bombtar — Kanten went 5-1 in games played against it at the October 2022 EX Mega Battle.

Weaknesses

Playing all the staple setup cards is nice, but since those cards are popular, people will be prepared for them, and you should be prepared to catch some hate as well. Cessation Crystal stops all the setup Pokémon from using their Powers, but you do have the full 4 Windstorm to deal with it. Much harder to deal with are lock pieces that come in the form of Pokémon, like Lunatone + Solrock, Jirachi ex, Sceptile ex δ. Jirachi ex is extremely troublesome as it's a Basic (requiring very little setup), hits Machamp for Weakness, and gets to attack for cheap if Machamp or Pidgeot are in play. You can buy some time against it by winning the coin flip on Voltorb's Thunder Wave, or Pow-ing it to the Bench and using Pidgey's Corner to trap something else in the Active Spot. Sceptile ex δ is deadly as it shuts off your comeback mechanic (Electrode ex), and 1HKOs Machamp even without you having taken any Prizes.

This deck doesn't have ways of spreading damage to the Bench (unlike Bombtar), which exacerbates the problem of dealing with lock pieces that are Pokémon. You have to spend Pow to flush them out, and the deck only plays 3 Pow due to space constraints.