From Bulbapedia, the community-driven Pokémon encyclopedia.
Saffron Pokémon Center is a type deck found in the Gym Challenge Strategy Guide. The deck is classified in the guide as an easy-to-build deck as it contains few rare cards, with the aim that a player of any age or skill level could complete it.
Sabrina loves to use Psychic Pokémon, and she also loves to play tricks on people. This deck lets her — and you — do both. Sabrina's Kadabra is a trick by itself. Its Life Drain attack can bring even a Pokémon like Giovanni's Nidoking down to 10 Hit Points in just one hit.
But that's not the only card up Sabrina's sleeve. Once you've Knocked Out one or two of your opponent's weaker Pokémon, use Sabrina's Hypno to put them back onto the Bench with half of their Hit Points already gone. Then you can use Gust of Wind and a couple more attacks to Knock Out those same Pokémon a second — or third — time. You could even use Mr. Mime's attack to damage one of those Pokémon while it's still on the Bench.
The last trick in this deck uses the Saffron City Gym Stadium card and Pokémon Center. Pokémon Center allows you to take all of the damage counters off of your Pokémon. But it also makes you discard all of the Energy from your damaged Pokémon. If you use the Saffron City Gym's power, you can pick up all of your Energy and put it into your hand before you use Pokémon Center. That way you can slowly reattach all of that Energy and attack again.