There is no permanent "free" full version of the game. It is a commercial product available on major digital storefronts: Giana Sisters: Twisted Dreams - GOG.com
Giana Sisters: Twisted Dreams - Game Details and Story is a fast-paced 2.5D platformer known for its unique "twist" mechanic that shifts the entire world's graphics, music, and layout in real-time. The Story: A Teenage Struggle Giana Sisters Twisted Dreams Full Free Download
: Resides in a dark, Gothic nightmare world. She mocks the monsters that once terrified her as a child. There is no permanent "free" full version of the game
: One night, a portal opens and Giana’s sister, Maria, is sucked into the Dream World and devoured by the dragon Gurglewocky . She mocks the monsters that once terrified her as a child
: The monsters Giana faces are often symbolic manifestations of real-world figures she struggles with, such as her father or strict teachers. Free and Legal Access