Hi kitty fox!I don?t understand wats wrong with this deck so could you 
pleas fix it

Pok`mon 13

2 x Mew(U.S promo 8 or 9)
2 x Mewtwo(U.S promo 3 or 14)
3 x Mr.Mime
2 x Hitmonchan
2 x Rocket?s Hitmonchan
2 x Kangaskhan

Energi 21

9 x Fighting energi
9 x Psykchic energi
3 x Double colorless energi

Trainer 26

3 x Gust of wind
2 x Scoop up
1 x Nightly garbage run
2 x Defender
2 x Imposter Oak?s revenge
2 x Imposter professor Oak
2 x Super energi removal
3 x Bill
2 x Item finder
3 x Computer search
2 x Energi removal
2 x Professor Oak

Strategy:

I try to get out Mew as fast as possible(If I fight with a deck that can 
evolve it?s Pok`mon)and if they evolve,I use devolution beam and on my next 
turn i use a
Imposter Oak?s revenge or a Imposter professor Oak , and so , I kill them.
If it is a haymaker , I try to get out a Rocket?s Hitmonchan , and when 
their pok`mon is very strong , I use Mr.Mime.
(the defender is to Rocket?s Hitmonchan)

ThAnkS
Don't see many people play with Imposter Professor Oak, these days. The only decks that successfully manage to pull off playing this card are Tickling Machine decks. I think you could improve your situation more if you remove the Imposter Oaks and replace them with more revenges. I'll also show you another nice combo I used in my Wigglytuff deck at the East Coast STS Qualifier in Chicago this past year. But, before I get too far ahead of myself, let's take a look at your pokemon choices.

First, let us decrease the number of Mr. Mimes you have in your deck to just 2 and increase your Mewtwo (Movie Promo) count to 4. We'll also drop your Rocket Hitmonchans in favor of one more normal Hitmonchan. You may also want to consider taking out Kangaskhan and playing with Sneasel instead.

Pokemon (15 Basic + NO Evols = 15 Total):
2 Mew
4 Mewtwo (Movie Promo)
2 Mr. Mime
3 Hitmonchan
4 Sneasel

For Energy, let's put in 4 of the Dark Energy so Sneasel and abuse the Beat Up attack, a little fighting and a little psychic.

Energy (15 Basic + 4 Special = 19 Total):
4 Dark Energy
6 Fighting Energy
9 Psychic Energy

That leaves us with room for 26 trainers. Let's focus on card drawing and stuff to disrupt our opponent's hand. The combo I mentioned earlier is Erika and Imposter Oak's Revenge. Play Erika cards so you can draw 3, then your opponent can draw 3. Play as many of these as you want, then finish it off by Imposter Oak's Revenging them... they lose all the advantage of gaining the cards that they got from the Erikas... removing its largest drawback and making it more powerful than Bill!

Trainers (26 Total):
4 Bill
4 Erika
2 Computer Search
2 Professor Oak
3 Imposter Oak's Revenge
3 Gust of Wind
2 Scoop Up
2 Item Finder
4 Plus Power

This does change your deck's theme slightly, instead of beating them up while unevolving their big guys... you just beat them up quicker with the backup of being able to unevolve. I didn't think you'd mind my making your deck faster and more dangerous ;). Best of luck to you!