Take a look at my deck!

[Dark_Absol]

Pokémon (23) -
2 Ralts R/S
2 Kirlia R/S and Sand
1 Gardevoir
4 Abra Rocket
3 Kadabra Base
2 Alakazam Base
1 Misdreavus Neo3
3 Gastly (a lot of sets!)
2 Dark Haunter
1 Dark Gengar
1 Cleffa Neo1
1 Chansey Aquapolis

Energy (20)
18 Psychic
2 Double Colorless

Trainer (17)

Pokemon Breeder
Wally's Training
Computer Search
2 Energy Search
1 Rocket Sneak Attack
4 Pokéball
1 Scoop Up
3 Bill
4 Gust of Wind

[Pokedragonfire]

I might put in some more energy cards if I were you (maybe remove some gust of winds or a pokeball) I think there are too many third stage evolutions, unless you put some more Wally's Training or a Pokemon Breeder, remove some and use a pokemon like Espeon who is a second stage evolution. And on my awesome fire deck, if I replaced the Magby and Magmar with two torkoal (EX Dragon) only for energy getting purposes. That's why I had the Magby. I don't want to use the Magby from Neo Genesis because it won't get me energy or stall for that long until I get some energy. But I don't like the Magmar ex you're right I should remove it, it's not that powerful for an ex pokemon and might give my opponent two easy prizes.

[Dark_Absol]

Thnx! I changed one pokeball for my other breeder and one gust of win for my rare candy.

My strategy:
Use Misdreavus to kill easy. Combined with dark gengar power, its very dificult to the oponent wake up. if all gets wrong, i use gardovoir and his great attack and power.

[Pokedragonfire]

Good strategy, but put in a Town Volunteers or something similar in case Misdreavus gets knocked out. And maybe some healing trainer cards in case the pokemon wakes up. What's a rare candy card what set is it from? Oh it's like a pokemon breeder.

[The Vince Knight]

The best thing to do wit town volenteers is to use it then use recycle or item finder and use town volenteers again and get back item finder or recycle then you'll get it back all the time!

[Bullados]

ok, you want this to be a Misdreaveous / Dk Gengar deck focusing on the OHKO? Here's the decklist...

Pokemon (15):
3 Gastly (Fossil)
1 Dk Haunter
3 Dk Gengar
3 Misdreavous
3 Cleffa
2 Tyrogue

Trainers (30):
3 Oak
4 Rare Candy
3 Computer Search
3 Item Finder
4 Chaos Gym
4 ER
3 SER
2 Town Volunteers
4 Focus Band

Energy (15):
15 Psychic

Chaos Gym is the most integral part of this deck. It keeps your opponent from switching out his/her Active AND prevents him/her from bringing your Gengar out from hiding. Card drawing with Oak, searching with Comp, recovery with Finder and Volunteers. This will not win tournaments. It is not designed to do that. It is designed to be a fun concept with a great ability to play in casual areas.