(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Further pushing the limits of X?V? puzzles comes a theme built around 8 and 13. Can you solve for the lucky and unlucky pairs in this grid from clover!?

PDF

or solve online (using SudokuPad)

Theme: Lixiviating Viriditoxin

Author/Opus: This is the 71st 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). Whenever an XIII or VIII, reflecting the numbers 13 or 8 in Roman numerals, is placed on the edge between cells, the numbers in the two adjacent cells must sum to exactly 13 or 8. (Pairs of cells without an XIII or VIII can have any sum value.)

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

Thomas Hits the GAS (highlight to view): 2:33, 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.