Games like Nicktoons Unite!

If you finished Nicktoons Unite!, the closest matches are Neighbours from Hell, Zack & Wiki: Quest for Barbaros' Treasure, Sam & Max: This Time It's Virtual, Tak and the Guardians of Gross and LEGO Island 2: The Brickster's Revenge. All 7 share its adventure genre and are ranked by how closely their themes and modes overlap.