In the Dreamwave comic book series, Leonardo is one of the four Teenage Mutant Ninja Turtles who live in the New York sewers with their father Splinter. This version of Leonardo is based heavily on the 2003 series' incarnation, and as such has the same history and some of the same experiences during the comics' run.
In the issue Bend It Like Turtles, Leonardo made the acquaintance of a young man named Dheeraj, who had run afoul of a small-time street gang known as the Thoogs. He gave Dheeraj a quick lesson on the proper way to begin combat, allowing the young man to gain the upper hand in a fight and rescue his crush Jaya from the Thoogs. After the fight, Leonardo was very pleased with what he had done, but was dismayed when Splinter suggested that the conflict was not over.
To this end, he chose to investigate the Thoogs further, learning of where they were squatting from Casey Jones. Upon arriving with his brothers, Leonardo heard that they were planning to sacrifice Jaya to the goddess Kali, and intervened by impersonating Kali alongside Raphael.