Simulating ecosystemic interactions
As argued by authors like Benjamin Abraham in his definition of an ‘ecological game’, few in-game environments are simulated in a reactive way that explicitly frames nature as more than an ornamental backdrop or a resource. While an exhaustive simulation of food webs and other ecosystem interactions is too complex for (at least commercial) games and, maybe more importantly, likely too unstable to ensure a consistent play experience, ecosystemic interactions can be selectively communicated to players by departing from gameplay conventions.
For example, in a game like Rain World, the fantastical creatures exhibit realistic ecosystemic behavior, e.g. managing survival needs, hunting, engaging in territorial fights, and navigating the world, even when not on-screen. Creatures like slug cats, lizards and vultures form a simple working food chain.
Sample games:
Rainworld