How A Mario Metroidvania Could Work

This video, I'm talking about how I think a Super Mario game in the Metroidvania genre could work. I go over plenty of stuff regarding potential gameplay, playable characters like Luigi, Princess Peach, and Toad, enemies like Bowser, Shy Guys, Shroobs, Crayzee Dayzees, and other things from the Paper Mario and Mario & Luigi franchises! With Mario & Luigi: Brothership releasing in November, and lots of franchise staples returning in The Legend of Zelda: Echoes of Wisdom, perhaps a new kind of Mario game with returning characters and species isn't that far-fetched!
Original versions of sprites are from Mario & Luigi: Superstar Saga + Bowser's Minions. Recolored sprites are by me.

0:00 - Intro
1:00 - Characters
2:58 - Gameplay, Start
3:20 - Gameplay, Groundwork
4:57 - Gameplay, Power-Ups
7:11 - Gameplay, Extras
8:26 - Story
10:28 - World
12:48 - Outro