Pentominous by Murat Can Tonta
or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a letter entry mode.)
Theme: Roman Numerals
Author/Opus: This is the 11th puzzle from guest contributor Murat Can Tonta.
Rules: Divide the grid into 20 pentominoes so that no two pentominoes of the same shape (including rotations/reflections) share an edge. A cell with a letter in it must be part of the pentomino shape normally associated with that letter. An inventory of possible pentominoes is given below the puzzle.
Answer String: Enter the letter associated with the pentomino occupying each cell in the marked rows from left to right, separating the groups with a comma. Use CAPITAL LETTERS!
Time Standards (highlight to view): Grandmaster = 3:45, Master = 5:15, Expert = 10:30
Solution: PDF; a solution video is available here.
Note: Follow this link for other puzzles involving Pentominoes.