Jesus this game is tedious. It was fun, for the first five-ten minutes, but theres only so much zombie whacking you can take before you get so bored and frustrated you start to question your life. This is probably a good thing in honesty, but shoddy game.
I was just doing the 'Last Chance on The Wall' side mission where you have to hang posters around Moresby of some guys missing daughter, or his location - one of the two. Got to the second poster place, cleared every zombie in sight. Went to collect the cash one of the dead zombies (oxymoron?) had kindly left for me, but unkindly, said zombie had died next to a manhole - so when I pressed square I went into the sewers. When I came straight back up ALL of the tw*tting zombies I'd just spent ages killing had magically respawned. F**k sake.
However, there seems to be a nifty little glitch I've noticed - If you have a gun without ammo, you can pick up and throw a gas bottle and you'll get 15 bullets for you to shoot the bottle/s to bits. Zombies will just walk though the explosion though., so it's only really worthwhile if you like (semi) pretty explosions. Saying that, it probably isn't a glitch and is completely intentional. Which is a bit odd.
What an infuriating game.