For many games (shooters etc) making a smart AI is relatively easy. What's hard is making an AI that's provides a realistic and interesting challenge. These "AI

For many games (shooters etc) making a smart AI is relatively easy. What's hard is making an AI that's provides a realistic and interesting challenge. These "AI"s don't use much in the way of machine learning however. I feel like this isn't what you're getting at though. Perhaps there's a specific example you have in mind?