What I mean by this is have you ever done a play through of a pokemon game. But you're only allowed to use one pokemon throughout the entire run. It's not like a nuzlock where if your only pokemon faints it dies and you are allowed to use other pokemon only for hm slaves. I have done one before. My very first one being when I was 11. I was playing pokemon white then I thought it would be fun if when I caught a Throh, from that point on i'd do an only run. I am also in the middle of one. A pikachu only run on y. I'm only at the 7th gym though.