Ok so I am not sure if I still have a decent deck here, but here it goes. Mewperior, of course you want to start with sableye and look for a pokemon collector. The most I will go up on pokemon collector is 3 due to the fact that you can get it out with sableye. I have Infernape in there for both Umbreon and Dialga G tech. He can one shot a Dialga G and before you level up he can take on Umbreon with doing 50 damage. Also his power is nice, it can get things out of the way you are concerned with. (mewtwo, Umbreon) I know I don't have a Mewtwo counter, but Delcatty may be able to do the job. Most Mewtwo Lv X in a deck are just a tech. They usually don't attack and if they do it takes a while to get those psychic you need. So you can two shot it with Delcatty if needs be. Also, you can keep getting it out of the active zone with Infernape 4 lv x. I may have crappy counters here, but I will take any suggestions!
Pokemon
4 x Sableye
3 x Mew
2 x Rhyperior lv x
2 x Infernape 4
2 x Infernape 4 LV.X
2 x Skitty
2 x Delcatty
Trainer/Supporter/Stadium
2 x Pokemon Collector
3 x Bebe's Search
3 x Energy Returner
2 x Snowpoint Temple
2 x Palmer's Contribution
Energy
3 x Call Energy - Special
3 x Rescue Energy - Special
2 x Darkness Energy - Special
5 x Fire Energy - Basic
5 x Fighting Energy - Basic
13 x Psychic Energy - Basic
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Pokemon
4 x Sableye
3 x Mew
2 x Rhyperior lv x
2 x Infernape 4
2 x Infernape 4 LV.X
2 x Skitty
2 x Delcatty
Trainer/Supporter/Stadium
2 x Pokemon Collector
3 x Bebe's Search
3 x Energy Returner
2 x Snowpoint Temple
2 x Palmer's Contribution
Energy
3 x Call Energy - Special
3 x Rescue Energy - Special
2 x Darkness Energy - Special
5 x Fire Energy - Basic
5 x Fighting Energy - Basic
13 x Psychic Energy - Basic
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