Bringing enemies to life

Enemies are more than just obstacles to be avoided. Good enemies give the player a sense that there is some underlying artificial intelligence (AI). The enemies seem to know when you are near, can chase you around walls, and wander on their own. In this chapter we will create three creatures that will inhabit the world, each with their own unique AI.

Summoning the Ghost Librarian

The first creature will consist of two parts: the overdue BookPile and the Ghost Librarian that protects it. If the player approaches a BookPile, a Ghost will spawn and chase the player. If the player gets too far away from the Ghost, the Ghost will return to the BookPile that spawned it. If the player attacks the Ghost, it will disappear and respawn from the BookPile. If the player destroys the BookPile, the Ghost it spawned will be destroyed as well.

1. Let's start with the BookPile. Create a new Sprite, spr_BookPile, and load Chapter 4/Sprites/BookPile.gif with Remove Background checked.

2. Center...