Black in particular stars as the film's main villain, Bowser, otherwise known as King Koopa, and the teaser opens with the villainous turtle waging war on a group of overconfident penguins.

Source: https://collider.com/how-to-watch-the-super-mario-bros-movie/

That film starred Bob Hoskins as Mario, John Leguizamo as Luigi, Samantha Mathis as Princess Daisy and Dennis Hopper as King Koopa (aka Bowser).

Source: https://www.chicagotribune.com/entertainment/movies/super-mario-bros-20230416-x2ean7jzarebjb5fnl3dbuw4im-story.html

The Blue Shell Koopa, Bowser's henchman in the movie and a constant thorn in Mario's side throughout, seems the perfect candidate to be introduced next.

Source: https://gamerant.com/mario-kart-8-deluxe-booster-course-pass-movie-blue-shell-koopa-character-antagonist-racer-dlc/

While some of the old favorites such as Goombas, Koopa (including a roller-skating variety), Dry Bones, Boos, and Lakitus are present, there will also be many foes that are unique to the Flower Kingdom, although not all have had their names revealed yet.

Source: https://screenrant.com/super-mario-bros-wonder-every-new-enemy/