Fighters is extremely slow but heavily armored. It shoots rockets which has a light damage but fast and follows player. Runners is extremely fast when in running mode. It enters running mode when the player is close enough to the Runners. Kamikaze follows the player (slowly) and have massive damage. Once it close enough to the player, it armed itself for a few second and create a huge explosion with devastating damage. Effector is a static enemy. It slows the player if the player is inside its range.
I also add a 'lighting' effect to destroyed objects so it looks like there is an explosion. I did this by creating a shader that (re)draws the background grid nearby the explosion. It also colored the grid/background color to suit the explosion color.
Next phase: fonts, GUI and menu.
PS: Just noticed the disabled health system. That is intentional to make the testing easier.
PPS: Still looking for artist! ;)