This post is part of the Genuinely Approachable Sudoku (GAS) series.
While this Sudoku looks like a proper classic, a special rule applies along each border between regions. Can you still find the one solution?

PDF

or solve online (using SudokuPad)

Author/Opus: This is the 31st puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, when considering the borders between two adjacent 3×3 regions, on one side all three numbers must be less than their direct neighbors across the border. (In other words, if adding < or > symbols to the three edges between adjacent regions, the three symbols must all point the same way.)

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:00; One party hat (🥳): 11:00. All other solvers earn a 🦕: consistent Condorraptor.

Thomas Hits the GAS (highlight to view): 3:01, 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.