I have ArmaII, but when I click download for the dayZ mod on steam it just brings me to the homepage. EDIT: do I absolutely NEED operation arrowhead?
As Jeanzl2000 said Operation Arrowhead is required. On a side note I'd recommend not using the DayZ Steam mod, instead use DayZ Commander
I'm aware, I was also using it until a friend of mine recommended DayZ Commander... It is waaaaaaayyyy better
DayZ Commander is an application used to launch DayZ and is much more advanced and user friendly than the Steam DayZ Mod It actually allows you to join more servers than the Steam DayZ mod does