I had this thing in SSBB were I'd create a storyline. I'd make the main character usually Lucario, Toon Link, or Pit, and the storyline would be dark vs light. All the characters that can have a dark color are evil, and the people who can do white are good. The storyline would usually start with Lucario being chosen because his dark color also has white, so he is more a hybrid. Toon Link would be the lord of darkness because he's black with red eyes, with red-eyed meta knight as his right hand. And Pit would be Pit of Death, being the betrayer for both sides, ultimately overthrowing Toon Link and killing the Queen of Light (Peach). That would force Lucario and Toon Link to team up, despite their hate for each other because Toon Link would constantly trying to kill him because Lucario has pure darkness in him that could cause the owner unlimited power. They would kill Pit, causing all the darkness to fade away, and Toon Link and Lucario would do one final battle as normal colors.
I can constantly do this storyline because it's made up as I go, and I create somewhat random battles, and the outcome would change the storyline progression. Sometimes I would rig the match and make the CPU level nine (I can usually face them, but I was acting dramatic which made it more difficult) or make it level three. And every round would be on stamina because that is much better for dramatic scenes, such as a final shot that brings them to zero.
I have loads of free time...