The Legend of Zelda: Mystical Seed of Courage
The Legend of Zelda: Mystical Seed of Courage (sometimes referred to with the fanon title The Legend of Zelda: Oracle of Secrets), was originally designed to be a sequel to both Oracle of Seasons and Oracle of Ages. Mystical Seed of Courage was supposed to be released several months after its prequels arrived on the shelf to form the Triforce Trilogy with the other two games. It was canceled due to issues involving how the games connected to each other. The project was soon scrapped after complications arose with linking the three games together.
Mystical Seed of Courage was supposed to feature Farore, similar to Din's appearance in Oracle of Seasons and Nayru's appearance in Oracle of Ages, and was to focus on time travel puzzles involving the time of day. Conversely, Oracle of Ages was originally going to focus on color-based puzzles, but absorbed the time travel theme when the former was cancelled.