Simply play by yourself if you want just one character throughout the entire thing you need to just kill yourself until you have 1 character left.
Beat Subspace Emmisary, and fight him in the Ruins.
no but only for the subspace emmisary just in case you got a character that you don't have for brawling on your team because there is a surpirise
the easiest way is to find him in the Subspace emmisary (adventure)
yes if you go on youtube.
I'm sorry but you can't do that but that would be fun if you could
Beat Classic mode with anyone after you clear the Subspace Emmisary.
By going through Subspace Emmisary, completing challenges, and playing Coin Launcher.
they call him r.o.b and I unlocked him by playing through all exept 1 in subspace emmisary
Coin launcher,trophy boxes in the Subspace Emmisary,and occasionally,in the Home-Run Contest.
Yes, he shows up as an enemy in The Subspace Emmisary. He also appears as an (invulnerable) Assist Trophy.
Raichu is not a playable character in brawl. The only Pokemon characters are the Pokemon Trainer, Jigglypuff, Lucario, and Pikachu. All of them can be obtained on a playthrough of the Subspace Emmisary mode, which is the easiest way to get them, as far as I know.
By completing SSE (Subspace Emissary or Adventure Mode.)