Hello gisli, and welcome to the Construct forum!
Before creating a game, i recommend you making a random project and find out what everything does. It's hard to make a game, without any knowledge, because if i say like this:
System
Conditon Pick Nearest
Diamond.Y, Diamond.X
-destroy
-set Dead_toggle to 1
..you probably dont understand it, right? Go ahead and read some tutorials!
-CX05