I remember it being the person with the good pokemon switching off the console at the right time.

Back in primary school I sacrificed my save file, pick a starter, clone it over and over again, repeat with the other starters till we had about 2 of each. Then cloned back the others to me.

From then on we could evolve one of each and keep another spare for cloning to others.

Someone somehow got a mew. So we cloned that to everyone too.