The Great Gianna Sisters III is a fangame based on the Great Giana Sisters released in 1988 by Laserdance of Rush. And it's a shot'em up game
The player's character is Giana (correctly referred to as Gianna) where she has to shoot as many enemies and grab any valuables for points as possible.
- It is one of the four games to not have its mechanics that is similar to the Super Mario Bros; the other three games are I Want More Diamonds, Giana Sisters: Twisted Dreams and Giana Sisters: Dream Runners
- Unlike the rest of the other games, the game's title has Giana's name correctly referred as Gianna.
- Ironically, despite being an unofficial sequel, The Great Giana Sisters III is released before Giana 2: Arthur and Martha In Futureworld.