Part of: This
"There are those who run in the face of danger..."
It shows people running away from a beam of darkness
"... There are those who cause danger..."
It shows Dark Pit shooting the very same wave, laughing. Bowser Jr is then shown chasing after the people with fireballs. Someone bumps into Wario. Wario then farts and laughs.
"... But ever so often there comes someone to stop the darkness. Someone to save the world"
Mario and Luigi jump on Bowser Jr, trying to get him to stop. Peach watches from the distance, and when a goomba comes up, she smacks it with her parasol. Samus' charge beam pushes back Dark Pit's. Link and Pit rush towards a group of Koopa Troopas, their swords out. Pikachu paralyzes a bunch of Metools, and Charizard shoots his fire at them. All of the heroes and Bowser Jr are knocked out. Dark Pit laughs with satisfaction. Suddenly we see Duck Hunt falling from the sky, the dog lands on Dark Pit, which knocks him out.
"The Good. The Evil. They all make..."
Smash Bros Warriors!