OpenTTD - An open-source clone of the classic game ...
Mad Father - Mad Father is a Role-playing, Puzzle, Adventure, and Single-player video game developed by Sen and published by Miscreant’s Room.
Simutrans - Simutrans is an open-source transport simulator.
Ib - Ib is an Adventure, Puzzle, Role-playing, and Single-player video game developed by Kouri.
Transport Tycoon Deluxe - Transport Tycoon Deluxe is a Business Simulation developed by Chris Sawyer and published by MicroProse.
Corpse Party - Corpse Party is an Adventure, Horror, Visual Novel, Puzzle, Role-playing, and Single-player video game series developed by GrisGris and published by XSeed.