you have too be signed in with other people then you can change evrything
In Call of Duty: Black Ops, to go on multiplayer you have to go to multiplayer on the menu that says: CAMPAIGN MULTIPLAYER ZOMBIES OPTIONS
the violence settings can be changed
There is. Just go to settings and make the "Number of enemies" higher.
You can't. I'm sure there will be a patch soon though.
When at the Multiplayer menu go to Playercard, then Edit Playercard.
If xbox360 you need to download something. (Xbox live)
no.
Online Xbox 360 play is not free and the online multiplayer mode of Black Ops is the only format for multiplayer
yes it will.
Yes.
you have to go on the option screen on the multiplayer menu
It automatically comes with the multiplayer!