YOU WILL NEED:

Fast Loop Bullets.mfa
This mfa contains all the objects you will need for this tutorial. Apart from the objects, frame 1 is empty, while frame 2 includes the finished code. Download here.

Torso (Active Object)
To animate the upper and lower half of a sprite independently, we must split it into two halves.

Legs (Active Object)
The Legs are the main character object, the Torso is simply positioned relative to the them.

Bullet (Active Object)
Holding shift will fire this bullet using a fast loop.

Impact (Active Object)
This object appears when the bullet collides with an obstacle.

Crate (Backdrop Object)
An obstacle for our bullets to collide with.