Game Development Reference
Global variables are shared by all the sprites, and local variables are for one sprite or clone.
You can think of global variables as values that are posted on the bullein board for all to
see. On the contrary, the local variables are like a leter. When a sprite is cloned, that clone
contains its own copy of that leter.
Adding scripts to Shield and
Shield protects and is also protected by the Spaceship. Each ime the enemy sprite collides
into it, Shield will lose one grid of power, displayed by Shield Life.