Here’s how I created the plasma balls the player and enemies in Gridblaster shoot. I have created it with The Gimp. I started by creating an image with a black background and creating a drop-shaped path.

02_01.png

Next, I converted the path to a selection (right click -> path to selection) and blurred it with a radius of 8 pixels (select -> feather). I then filled the selection with solid green.

02_02.png

To create the lighter center, I created a new layer, shrunk the selection by five pixels and filled it with a lighter color (#e7fdb1 in this case). The result is an elongated plasma ball.

02_03.png

I also created a small green plasma ball in a similar manner, wich I used for the particle effect that forms the tail of the projectile. How I did that if for the next tutorial; I want to keep the Gimp tutorials separate from the particle tutorials.