Author/Opus: This is the 36th puzzle from our contributing puzzlemaster Serkan Yürekli.
Rules: Divide the white cells into tetrominoes so that no two regions sharing an edge are the same tetromino (L, I, O, S, or T considering rotation and reflection). Regions may contain at most 1 cell with given letters; regions with such a cell CANNOT have the same tetromino shape as any of the letters in that cell. Also, see this example:
Answer String: Enter the letter of the tetromino region for each cell in the two marked rows from left to right, separating the rows with a comma. Use CAPITAL LETTERS for L, I, O, S, and T.
Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:30, Expert = 5:00