Transport Tycoon is a 1994 PC (DOS / Windows) game from Chris Sawyer, catalogued here for 5 defining game mechanics.
PC (DOS / Windows)1994Complexity 80/1002D IsometricCult classic
Transport Tycoon is a business simulation game designed and programmed by Chris Sawyer for MS-DOS. It was published by MicroProse in November 1994. Using an isometric 2D view with graphics by Simon Foster, the player acts as a transport company owner, who competes against rival companies to make as much profit as possible by transporting passengers and various goods by road, rail, sea, and air. (via Wikipedia)
The game mechanics of Transport Tycoon
Economy Buy SellResourcePlayer earns and spends currency at merchants; price and value decisions are meaningful.
Resource HarvestingResourcePlayer or AI units collect raw resources from the world that fuel construction, production, or advancement.
Upgrade PurchasingResourcePlayer spends accumulated resources or currency on permanent stat or ability improvements chosen from a menu.
Simulation TickSimulationWorld state advances on a regular clock independent of player input; player decisions are responses to the advancing simulation rather than…
Unit PathfindingSimulationIndividual AI units navigate around obstacles to reach dynamically assigned targets.
Each mechanic links to how to build it in Godot, with the retro games that share it.
Study the source
Open source (GPL-2.0). OpenTTD is a full rewrite of Transport Tycoon Deluxe, playable with its free OpenGFX/OpenSFX assets. https://github.com/OpenTTD/OpenTTD