Well what you can do, for that is use events.
First Add a even to the map you are on, and for the even grahpic set it to a monster. After you do that you can set the direction of the way the monster will move but changing the Autonomous movment. If you want the enemy to move towards that player. You will change it from fixed type to custom type.
Then the button Move route will be avabile to you under move route set it to,
Move toward player. After you do that you can set the speed at which the monster will move at, and how often that happens. Ok after you do that go to the List of event commands and go to the thrid page. See where it says Battle processing push that button and set up the monster group the player will be figthing. After all that is done set the event tigger to either player touch are event touch.