Levels 1-4
The first levels are all about getting points. How they are handled depends on the skill level of the players, however.
Obviously, each person takes a window. During these levels you should NEVER buy a weapon, its just a waste of points. The way to get the most points out of this would be to shoot each zombie 3-4 times with your pistol and then use your knife to finish the job. This should get you about 160-170 points per zombie in the first level, and possibly a bit more in the few levels after that. You should also let the zombies take off some boards and even let them in during this time. Though, I would not recommend letting them in during levels 3-4 because with the increased amount of zombies, the chances of getting knocked down are much higher unless you are very skilled. Getting knocked down in the early stages should be avoided at all costs because it is a huge waste of points. It is far better to lose a few points from boards than to go down and lose even more.
If a bomb comes up, I'd recommend waiting as long as you can before taking it during these levels. Kill as many zombies as you can, and then use it. 400 points per person shouldn't be passed up.
During instakill you should NEVER use anything but you're knife. It's a complete waste of points and ammo.
Grenades should only be used for an emergency situation.
Levels 5 - 12
At the end of level 4, open the door to the double-barrel shotgun and the next door to the furnace room. Grab either a thompson or double-barrel shotgun. Depending on whether you have time or not, you can also clear the debris at the top of the stairs by the furnace room and go to the courtyard to turn on the power. If the dogs come at level 5, you can go to one of two places. If you haven't made it to the courtyard, then everyone should go into the corner in the furnace room. Otherwise, everyone should crowd around the mystery box in the courtyard. Both of these are good spots for funneling in the dogs and making quick work of them while minimizing deaths.
(Note: The other door leading to A should be kept closed to open up opportunities later)
A lot of people seem to want to line up against the back wall (the door to teleporter C) to fight the dogs, however this way is much less safe and allows the dogs to pile up on a single person more easily. It's not going to get you any extra points, either, so it's best to pick a corner.
The safest way to play these levels is for everyone to stick together in the courtyard. It's very easy to line up headshots on zombies with the thompson as they come in. I would recommend the thompson over the double-barrel shotgun because the thompson will take a few quick shots to kill a zombie, giving you a few +10's for earlier hits then +100 for a headshot (which you'd better get). The double-barrel shotgun, however is a one-shot kill, so the most you'll get is 100 points, and if you miss you'll only get about 50. Though, it may be beneficial for at least one person to keep a double-barrel shotgun around. Allow yourself plenty of room to back up.
Everyone MUST get betties as early as they can. Level 6/7 the latest. Place your betties around the entrance to teleporter C. This will give you an area to fall back to if you get in trouble. (In an extreme case, open the door to C if you really need to get away.)
Perks should be a secondary priority in these levels. They shouldn't really be necessary. You can survive without juggernog so long as you play it safe and give yourself room to fall back to when you're outnumbered. I personally usually buy speed cola before juggernog. This is especially helpful (and pretty much necessary) if you're using the shotgun.
Visits to the mystery box at this time should be kept to a MINIMUM. You don't really need new weapons during this stage. The most you will need from the box would be monkeys (which it usually hands out early) and a new weapon if you're out of ammo. If you happen to get the Wonderwaffe, ONLY use it when you absolutely have to. It is not going to fetch you very many points per kill, and during these stages ammo should not be a problem. The same thing applies to the ray gun. I've seen people waste thousands of points constantly on the box trying to get a good weapon. You will need those points later.
http://pure-rage-gaming.com/images/Der-riese_layout3.jpgLevel 12 is kind of an arbitrary choice. It really depends on when you're ready to link up. Level 12 is mostly likely the LAST level you will want to spend completely in the courtyard. At this point you'll need to get a crawler and link up. The two doors that should be kept CLOSED at this point are the one at the beginning near the mainframe (leading to A), and the juggernog stairs. The reason for this is so that the zombies around A must funnel through that one pathway no matter what. These doors can always be opened later if needed. (The door by the mainframe will almost always be opened by 30, and the juggernog stairs never.)
Max-ammo: ALWAYS throw your monkeys when a max ammo appears, as you'll get them back. And ALWAYS try to wait for your teammates to reload and throw what they want to throw before you grab it. NEVER grab a max ammo while a teammate is down if you can help it. Teammates in need of reviving will not receive the ammo while downed. This is especially important later in the game when ammo is at a premium.
Bombs: I have mixed feelings about using the bombs during these rounds. It's not entirely necessary, and you might get more points not using them, but I use them anyway. Though, obviously don't use a bomb if it will kill a crawler.
Instakill: You should almost ALWAYS use your knife during instakill here. This is a very good time to take advantage of these because the zombies aren't too powerful. You should only use another weapon when you're heavily outnumbered, which you shouldn't be. And if you must use a weapon, use your pistol if you still have it.
When the dogs come again, just as before, everyone should crowd around where the mystery box is (or was).
Levels 13 - 22
By now you should have linked up and perhaps even have an upgraded weapon. The roles of each person now become much more specific. The strategy here is to set up camp at teleporter C. I'm going give each player a number for reference.
Each player should place their betties on the catwalk starting at middle between the stairs and the cage, leading down the stairs and the floor next to the stairs (if you can build up that many). This will create a good path to fall back on, and to protect Player 1's back. Everyone should have a bowie knife.
Player 1: Will play at the window on the catwalk at C. Keep all zombies from coming in through the window and shoot shoot down into the courtyard. It may be very helpful to save your pistol throughout the entire game and upgrade it first. This is a great spot for launching grenades at almost any point around C so you can cover your teammates if they get overrun.
Players 2,3: Will play at the main door to teleporter C. Not the gate thats opened, but the one inside. Both players should have some sort of MG and SMG. Playing just inside the door will give you plenty of room to back up and reload. At this point, picking up an STG44 may be a good idea to have ammo always available to you.
Player 4: Plays in the underground tunnel at C, guarding the window. This position has a little less action than the others, so you can take a few shots out into the courtyard through the hole in the wall, however, the top priority is to keep the zombies from getting in that window.
Player's 1,4 will try to trap zombies in their windows in addition to trying to get crawlers. Trapping the zombies in the windows is much better than crawlers in that they are much less likely to randomly drop dead, and each player can take a turn on the window for points while the others take care of business between rounds.
It gets much easier to die in these rounds, and the cost of getting knocked down increases greatly from losing perks, so do not hesitate to back up when needed. The electric fence should not be necessary in these rounds, unless ammo has become an issue. During the intermediate time in these rounds when you have a zombie trapped or a crawler, everyone should make an attempt or two to try to get monkeys or a raygun. I would not recommend taking more than a few tries though. It *seems* like these weapons come up when they're more needed, however, its difficult to say that conclusively. My theory is just to save your points. A good way to generate points in these rounds would be using the bowie knife as much as possible. The earlier rounds it'll be a one hit kill, and later rounds all you need to do is take a few bodyshots and knife. So, long as there are only a few zombies in your vicinity at the time, this should be safe to do.
All powerups should be taken from here on out. It is also very important that everyone throw their monkeys and grenades when a max ammo comes up. Not doing so is now a waste on ammo. This will also make it much safer to grab the max ammo. Everyone should also have quick revive at this point. If needed, throw a monkey if someone gets knocked down and its not safe enough to revive them. There should be a system worked out for who throws a monkey when, so they're not wasted from multiple throws.
By the early 20s, almost everyone should hopefully have a raygun and monkeys.
When the dogs come during these rounds, and here on out, everyone should go into the underground tunnel at teleporter C and go all the way in the back. The dogs will funnel in and be incredibly easy to kill and it will just get easier as time goes on.
Levels 23 - 30
This stage begins when it becomes too difficult to hold the front door at C. All players will fall back to the catwalk. The player guarding the window will remain at the window, continuing to trap zombies at the window while shooting down into the courtyard with a raygun. The player with the wonderwaffe will stand on the middle of the catwalk. The remaining two players will stand at the top of the stairs with MGs/Rayguns. The player with the wonderwaffe will shoot out the window, or help the players on the stairs if needed.
In these rounds, the player with the most points will be designated to make runs to the electric fence. While he does this, only one player should be needed to watch the stairs while the other two cover the fence runner until he's safely back. This same procedure should be followed to retrieve powerups. One player must watch/listen for the green light to come on for the electric fence so that it may be thrown again as soon as possible.
You might want consider waiting to upgrade your raygun if you get one. In these later levels max ammos are much harder to come by, so upgrading it when you need ammo can help a lot. I wouldn't recommend waiting too long for this though. The closer you get to 30, the harder it is to last a whole round even with an upgraded raygun.
Levels 30+
You may need to do this before 30, depending on how much ammo you have. This is where all your points that you've amassed will really come into play. In general though, it is incredibly difficult to make a stand anywhere for an entire round, so you need to start running. It's a good idea to start running when you're dropping below 25% ammo and the round is nowhere near over.
Once you've determined you need to run.. run. Go to the teleporter and hit it when the zombies get in your face. Try to wait until there are as many zombies on you as possible to get as may kills out of the teleport as you can. When you're at the mainframe pause for a moment to see if it gives you anything, and grab as necessary. (double points and the hammer are probably not worth the risk). From there you have two choices. You can either run to A and hit the fence behind you, or run to the furnance room, hitting the fence behind you. If you choose the furnace room, wait in there for a few moments after hitting the barrier, so that the new zombies spawn downstairs (mostly), then run up the stairs. (Don't wait too long though, or you may be trapped by any possibly spawning upstairs) From there you can either run to B, or drop down and back to C. If you run to A, it is important to hold out there longer than you would at B or C. Once the electric fence turns off, get some grenades down into the hallway to slow them up. Teleporting too early might get you into trouble at the mainframe from stragglers coming through, so take caution. Follow some sort of rotation between teleporters like this (C -> B -> A) taking turns hitting the barriers. Ideally, you should be doing this until you exhaust your points, at which point the game should be just about over.
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