Yes and no... You can do that "offline" but you have to have a friend or something along those lines playing as a human. But no you can not be infected by yourself.
yes
zombie mode is on ps3 you dummy
No. Unfortunately not
yes yes
Not on the same xbox/ps3 no unfortunately.
wa bybi
No
l4d2 it has more zombies and its more funner.
Buy both but i prefer L4d2 if you want to kick some zombie @ss and if you want terrorist @ss by Mw2 btw im buying mw2(on ps3) first then l4d2(probably PC)
No, it is not possible to clone a zombie kitten.
Yes, you can, but I'm not sure, if its possible to play with friends offline...
Unfortunately, it is not possible. People make themselves offline on purpose for privacy reasons.