Now I've been watching, playing, and reading the series for a while and I have an idea on the lifecycle of the aliens, xenomorphs, bugs, serpents, or whatever they have been called that I might have missed. I will gladly take any logical comments into consideration. If I make a mistake, point it out for me will you.

royal egg

enhanced facehugger

queen chestburster

preatorian cocoon

preatorian

crystalis

queen/ravager/carrier

egg

facehugger

chestburster

cocoon

Alien