In Odd-Even-Big-Small Sudoku there are lots of category clues to the first two numbers inside the grid. Can you figure out how those make a unique solution?

PDF

or solve online (using SudokuPad)

Author/Opus: This is the 20th puzzle from Bill Murphy, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 8 into each cell so that no number repeats in any row, column, or bold region). Clues outside the grid give the nature of the first two cells seen from the direction of the clue as follows:
O for Odd = (1,3,5,7};
E for Even = {2,4,6,8};
B for Big = {5,6,7,8};
S for Small = {1,2,3,4}.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): TBA; One party hat (🥳): TBA. All other solvers earn a 🦕: TBA T-Rex (for now).

Thomas Hits the GAS (highlight to view): 2:59, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF; solving video with explanation to be added later from GAS team.

Note: Follow this link for other less common variations of Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.