Making enemies follow the player, find the best route (pathfinding) and other kinds of behaviour can be done with known algorithms like genetic algorithms, A* (A star), flowshop, etc, usually using prolog. Is there a way to use prolog programmation to make AIs on Unity?
It is possible using a compiler and a prolog program, such as P# and other (references below). Some material to make better artificial intelligence and example codes:
guide to prolog programming
prolog in C# http://sourceforge.net/projects/cs-prolog/
A Star (A*) example
Aron Granberg's pathfinding http://www.arongranberg.com/unity/a-pathfinding/
unity fps tutorial (includes a working enemy with simple AI implemented) http://unity3d.com/support/resources/tutorials/fps-tutorial-part1