What kind of game is the A.I. for? Street Fighter, StarCraft, Doom, and Tetris Attack are all going to have significantly different A.I.
I am guessing you could try having the enemy unit measure distance from the player. If they are in range attack once every few seconds. If not in range move toward them.
im Making a Free roam Space game. I want an AI that will Patrol an Area until you get in range. Then, No matter where you Go, it will Follow you and Attack.
