|New Super Mario Bros. Underwater Universe|
New Super Mario Bros. Underwater Universe is a game in the Mario Series. It is also a game in the New Super Mario Bros. series.
Bowser kidnaps Princess Peach, and retreats into an underwater universe. Mario, Luigi, Blue Toad, and Yellow Toad chase. They must make it through 8 underwater themed worlds (and a bonus world for completion bonus), to save Peach.
The gameplay differs from many New Super Mario Bros. games because EVERY level is an underwater level. There are little bubbles of air, and your character must grab them to get air so they don't drown. Also, every familiar boss will be fought underwater, using underwater weapons.
Yoshi was originally going to be able to be ridden underwater, where he would swim slightly faster then Mario and friends. However, this was scrapped due to budget restraints.
The game got mostly positive reviews. Many people complimented that Underwater levels, something that was generally hated, was made into something great.