Web app which allows you to create simulations customizable on the fly by adding different variables and "laws".
It has an "AI" component which acts as a simple neural network (with UI where you can change the amount of inputs, hidden layers and outputs) - but to train it you have to write your own code - see example training code.
https://brun0ne.github.io/simulathrone/
This code is available on MIT License, so feel free to use it or fork.