I.D.I mod for Half-Life 2

This mod is a single player for half-life 2. There are diferent selections of campigns ones infected where you escape a horrible incident worse than black mesa and headcrabs were luanched everywhere infecting innocent people. And the combine have changed battle plans and now kill everything in sight and you must protect as many people as you can.
Another is defend the base where you must protect a base with valuable stuff inside and you must protect it from any enemy which comes along.

next is invasion which i cant tell you the story but a city you live in gets invaded by enemies and you must survive the new threat.