Tech Decks, such as Groudakion (Steven Shirely), Eelkou (Rhys Williams) and EmpoleoPhan. I was playing Zeelturn (Zekrom, Thundurus, Eelektrik, Lanturn, Stunfisk, Zapdos, Mewtwo) and I somehow managed to make it 2nd place in seniors even though I played people who designed decks just to beat mine. Both 1st and 2nd place in seniors were playing similar decks with Eelektrik energy accelerators. This clearly shows the Fighting Techs aren't working.
Something that did work against Eelektrik was Raikou EX. Rhys Williams played it and made 1st place.
It has a bulky 170 HP and has a second attack called volt bolt. That attack can do 100 damage to ANY Pokémon on your opponents side as long as you discard all lightning energy attached to Raikou. This by itself isn't a good attack due to it's high energy cost of 3 and having
to discard at least two 3rds of it's energy. If you have: 2-3 Eelektriks ,who can get energy from the discard to the bench and you have 2 Raikous ; a Skyarrow Bridge stadium card you can consistently Volt Bolt turn after turn.
The only problem is that attackers in Zeels decks have over 100 HP such as Thundurus and Zekrom.
My version of Rhys Williams's deck list
2 Tornadus EX
1 Mewtwo EX
4 Dual Ball
1 Pokémon Collector
4 Pokémon Catcher
2 Level Ball
4 Junk Arm
1 Plus Power
1 Random Receiver
2 Skyarrow Bridge
4 Professor Juniper
3 Professor Oaks New Theory
4 Double Colorless
2 Rescue Energy
4 Tynamo and 4 Eelektrik is purely so you can have as much chance to get them as possible as early in the game as possible. Thundurus is to get the energy out of your deck as soon as possible.
Tornadus EX is in there incase Fighting Tech Decks continue to get played. Mewtwo is a alternate attacker and to beat other mewtwos. Skyarrow Bridge makes all Basic pokemons retreat cost 1 lower.
The rescue energy is in because Volt Bolt says you discard all lightning energy attached to Raikou with a cost of Lighting,Lightning,Colourless. Therefore with Rescue energy isn't discarded.
This decks uses Eelektrik itself so in mirror match you need as much speed as possible! It'll be like 2 decks with 4 mewtwos playing each other.