Sudoku86

Sudoku86 is a 16-bit real-mode Sudoku puzzle game created by developer Mateusz Viste and released as open-source freeware in 2014. Although written decades after the MS-DOS golden era, it was intentionally designed as a modern retro-release built specifically to run on ancient PC hardware from the 1980s.
The game was programmed using Turbo C 2.0 and tailored for 8086/8088 processors, requiring just 50 KB of conventional RAM and DOS 3.0 or higher. The visual presentation utilizes a clean $320 \times 200$ resolution supporting CGA, MCGA, or VGA graphics modes.
Gameplay faithfully implements the classic logic puzzle rules where players fill a $9 \times 9$ grid so that every row, column, and $3 \times 3$ subgrid contains the digits 1 through 9. It is entirely mouse-driven, relying on a two-button mouse interface to select cells and input numbers rather than complex keyboard shortcuts.
The base game includes 100 pre-installed Sudoku puzzle grids of varying difficulty levels. Designed with lightweight localization in mind, it supports multiple language interfaces including English, German, French, Turkish, and Swedish.
Due to its ultra-low system footprint and strict compliance with original PC standards, Sudoku86 has become a popular included utility in modern FreeDOS distributions and retro-computing showcases.

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