Well, i have only beaten four of the silver symbol leaders, but i beat Noland the easiest.
I had this Grumpig, it knew Psychic, Ice/Fire/Thunder Punch.
It took out Noland's Piloswine in two fire punches, his Seadra also fell to my Grumpig, and his Primeape was defeated by Psychic.
My Breloom and Poliwrath werent even used.
I beat Lucy, Greta and Tucker with pure luck.
my battle versus Tucker was my Swampert & Alakazam vs his Swampert & Charizard.
My Swampert took out his Swampert using Surf, but Tucker's Charizard took out Swampert with Rock Slide. My Alakazam took out half of his HP, he almost killed me with Earthquake, but my Alakazam survived and took Charizard out with Psychic.
I lost to Lucy four times, before finally obtaining victory from an unexpected friend. My Pikachu with Light Ball.
I took out the Seviper with Alakazam's Psychic. But Seviper's Crunch left my Alakazam with few HP, her Shuckle took Alakazam out with Wrap. I sent out Aggron, and easily took out Shuckle with Iron Tail. Her Milotic took out Aggron with Hydro Pump, and my Pikachu took out Milotic with one single Thunder.
Greta also gave me a run for my money. I took out Heracross with Swampert's Surf. Umbreon took out Swampert with Faint Attack, and i sent out Alakazam and damaged Umbreon with Shock Wave, but Alakazam fell too. Aggron took out Umbreon with Iron Tail, and took out Shedinja with Aerial Ace. I was so damn lucky i taught Aggron Aerial Ace.