sonic and toad
25
25
get all the characters
All of them.
play 1000 vs matches to unlock character 25, Mr. Game and Watch. There are no characters after that.
Technically yes sheik is a separate character making 26 characters.
The last two characters are the custom characters.
The last two characters you can buy are Bando and Anbu Kakashi.
If by "Koopa" you mean Bowser, he is playable from the start. "Purin" or Jigglypuff is one of the easiest characters to unlock
Beat the adventure with jiggy puff, pickachu, and pichu
No
No he is not.