Pokémon
Yanma x2
Yanmega ex x2
Magnemite x2
Magneton x2
Magnezone x2
Hitmonlee x2
Hitmonchan x2
Marshadow x2
Farfetch'd x2
Chatot x2
Strategy
Here's a deck list to help with the Zero Trainer Solo Battle Challenges : PTCGP
Use only Fighting energy.
The idea is to be aggro with Farfetched or Chatot start. That's the preference as they deal 40 dmg for one energy but you can start hitmonlee/hitmonchan too worst case scenario. Depending on what you draw you can put energy on Yanmega/Marshadow on the bench. Magneton will generate his own energy obviously and will be the pinch hitter if necessary.
My games never made it that far. They normally ended with Marshadow