Urgent question

[Dentafrice,]

Me and my dad want to play against each other.

I have a valid steam account and a set of CD's

but if I make my own server on LAN can he play without a valid steam account?

[kyle♥]

I think he could log on your Steam account while you're in the game. But other than him not having a Steam account, I don't think it's possible via LAN.

[Dentafrice,]

Nevermind now, my laptop wont run steam its stupid.