Water Star Adventure is a ROM hack for Super Mario 64. It is the seventh installment of the "Star Adventure" hack series, featuring 7 courses with 30 stars including a Bowser fight.

The gimmick, as the game title implies, it has a new mechanism using water physics that the player can use to swim to navigate unreachable places. The plot is bound with philosophy and religious metaphors and most stars and NPCs will tell the player have more or less relevance in the gameplay.