The virtual world: the Monsters
Have the concept of a general set of abilities such as ‘interact with’. These can be applied to anything in the world. It returns some value or changes a state. The Monster must be able to judge whether it prefers that state, and ranks that action as better or worse then it ranked it before.
This is a nice idea but may take many generations before a single working Monster evolves.
The environment must be diverse enough to allow ‘niche’ specialisation. Complexity is the key to non determinism and variation.