All I do lately is play Farm Grief. If you have XBL, add me: StripleR675
My Strategy:
Wave 1: I run around and try to knife zombies and steal kills from enemies when possible (I try not to steal from teammates). If I don't think I can reach the zombie to knife before an enemy gets to it, I shoot with the 1911 (aiming for headshots). At the end of the round, I try to repair doors for extra points. If I see an enemy has just started repairing a door, I try to knife them once or twice to knock them out of the way and repair the door myself(I do this at the end of every round). NOTE: There is a timer where you get points for repairing doors which increases for each wave. If you see that you're getting no points for repairing a door and nobody else is around you, it might be better to wait until the beginning of the next wave so you get some points.
Wave 2: Depending on the situation, I try to shoot the zombies about 5-8 times to get some extra points before knifing them. Totally situational because I might be alone with a few zombies and can shoot at will or be crowded with teammates/enemies/zombies where it's a knife-slashing free for all. By the end of Wave 2, I should be out of 1911 ammo (except on the rare occasion we would have picked up MAX AMMO). Fix doors (and/or steal doors from enemies) for extra points and I usually have around 1200-2000 points to spend at this time.
Wave 3: I check if the doors are open to the house. Since it costs 750 to open it, I prefer if someone else (hopefully an enemy) opens it instead. If it's open, I go ahead and run upstairs to purchase the MP5 and start running around getting as many headshots as possible. If the doors are still closed, I hit Select to see the Player stats. If I see that I have a lot more points than most of the other players, I take the sacrifice and open it myself (assuming I have at least 1750 to open the door and purchase MP5). If anyone else has a lot more than I do, I run around trying to knife zombies until I hear the mystery box sound indicating that the doors are open. By the end of Wave 3, I should have my MP5. I try to conserve ammo with it by burst firing while aiming for headshots. NOTE: Anytime I'm upstairs in the house getting MP5 ammo, jugg-nog, or mystery box, I check to see if an enemy is using the mystery box while standing up and not in the corner by the mystery box and the wall. I knife them a couple times and can usually get them to drop off the ledge before they pick up the item. Then I go to the door and lay down and try to block them off until they are unable to get their item.
Wave 4: Either at the beginning or during this wave, I should have at least 3,000 points. I use it to reload my MP5 ammo and get Jugg-nog. Headshots with the MP5 all day unless we get INSTA-KILL and then I try to knife the zombies.
Waves 5-11: I save up and get the rest of the perks in this order: Speed Cola, Double-Tap, and Quick Revive. IMPORTANT: I always keep an eye on my points and MP5 ammo while doing this. Even if I save up the 3K for Speed Cola, if I'm low on MP5 ammo, that takes priority over perks. Once I have all the perks, I make sure I have enough ammo for my MP5 and then it's off to the Mystery box. I try to have at least 1,450 points before hitting the Mystery box after that in case I get something I don't really want or is not a gun. Then I still have the option of buying MP5 ammo for 500 afterwards as a backup.
Waves 12 & 13: I've played a ton of games and most of them end in these two waves. On one occasion, I made it to round 14. If people start Timing out or leaving the game early, it might end sooner, but more often than not, it ends at 12/13. Most of the strategy to winning the game comes into play here. There is a lot of randomness here due to what I can or can't get out of the mystery box, the possibility that I may have gone down already or will go down and lose all my perks, and how many players are remaining and not down. I can't really give my strategy because it changes depending on the aforementioned situations.
In most scenarios I've seen, everyone except for one person is left at the end of one of these rounds. They basically just run a slow circuit by running backwards, stop at a bottleneck, throw a grenade and aim for headshots in the zombie group, when they get too close, run for the next bottleneck and do it again. I usually start by running slow circles around the truck in the middle of the map and round up the zombies. Once it starts getting hairy, I move into the barn area with the two stairs. I run back to the second set of stairs furthest from the entrance. Hopefully there should be no zombies, but there could be a few which spawned at the top that I quickly kill and turn my focus back towards the stairs. I'm at the top and cook a grenade. Throw it at the bottom of the stairs and then go for headshots. I then jump down to the bottom using the area with the broken railing and head slowly towards the house. I headshot until they get too close and move to the top of the stairs in the house. Do the same thing I did in the barn, but get more MP5 ammo. Wait in the corner of the upstairs room facing inward as nothing can get me from behind. Shoot approaching zombies there until they get too close and drop down. This completes my 'circuit' and I do it over and over again until I win or die. IMPORTANT: Throwing grenades at a group of zombies usually results in halfies/crawlies. This makes the game a bit more difficult as they move slower and don't stay in the bigger group that I'm kind of corralling around. I've gotten into hairy situations with a group of halfies blocking the forward movement of my circuit and the walking zombies blocking me from behind. This is why I'm usually hesitant to use the grenades sometimes, but I try to limit it to the stair sections and when I come back to that part of the circuit later on, I try to run ahead of the walking zombies to clear out the halfies first.
