20 pokemons

1 Kadabra (strong attack ,can recover it's HP)
2 Abra (to evolve into Kadabra ,can paralyze opponents)
2 Jynx (strong attack)
1 Hunter (dream eater is strong ,can hypnosis opponents)
2 Gastly (to evolve into Hunter)
2 Drowzee (can confuse opponents)
2 Tanela (can paralyze and poison opponents)
3 Koffing (can poison and confuse opponents)
1 Beedrill (strong attack)
1 Kakuna (High HP)
2 Weedle (can poison opponents, to evolve into Kakuna)
1 Metapod (High HP)
2 Caterpie (can paralyze opppnents ,to evolve into Metapod)

10 Trainer cards

2 Bill (to use after pokedex)
1 Potion (help chansey stay longer)
2 Revive (if a good pokemon is knocked out)
1 Plus Power (to make our attacks stronger)
1 Gust of Wind (to get opponent's weaker pokemons out)
1 Pokedex (to organize the deck)

13 psychic energy, 16 grass energy, 1 double colourless

To paralyze, confuse, poison and make your opponent asleep, then to attack them with strong pokemons like Kadabra and Haunter.