Sudokuvania: Digits of Despair

Here is an excerpt from Sudokuvania: Digits of Despair's description on the game's official website:

This is a labor of love combining sudoku with my favorite video game genre - Metroidvanias. MVs are known for featuring exploration, gaining new abilities, and difficult boss fights, and I noticed the similarity to grid-based puzzles as soon as I started setting them. So, I present Sudokuvania: Digits of Despair.

Not just a big puzzle, Sudokuvania is a puzzle hunt in and of itself. As you clear the 40x50 map of dynamic fog, you will uncover new clues and new rules. Some cells' contents can only be found by solving linked Boss Puzzles. There is even a bit of a story, although I wouldn't call it compelling by any means. All in all, Sudokuvania is over 20 puzzles in one!