How to get Machamp in Pokemon Ash gray?

I know you trade Machocke in regular games but how am I supposed to do that in the rom hack "Pokemon Ash Gray"?

1 Answer

Trade evolutions in AshGray evolve through having a high happiness level instead. Source

You can increase the happiness of a Pokémon by performing certain actions like walking with it or using friendship increasing berries. You should be able to achieve a high enough friendship level through normal play. See the Gen III mechanics for a comprehensive list of all the ways to increase friendship.