You can not play Half-life mods with Half-life 2.
You can not play Half-life 2 mods with Half-life.
To play the current Half-life itteration of ZP, you will need half-life
To play the next itteration of ZP, which will be for half-life 2, you will need half-life 2.
- Retired Playtester, Server Operator & Moderator
My doctor says that I have a malformed public-duty gland and a natural deficiency in moral fiber, and that I am therefore excused from saving Universes. - Douglas Adams