Zombie Escape Theory
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This theory is for the Counter-Strike: Source's zombie escape mod. This is intended to high a headlights to anyone interested in making a zombie escape map.
Introduction
Motanum, and I have made 3 (Almost 4) zombie escape maps, I have mapped for a year, and I take a close look at my maps. This tutorial contains information, which I hoped I had known when I started mapping for Zombie Mod. I will use some maps names as example. I am sorry if your map is mentioned, but instead of ranting about how bad my maps are, take a deep breath, and maybe realize there is something you could change about your map to make it more enjoyable.
Always keep in mind the objective of a zombie escape map which is the escape. The simple way to divide an escape map is in three: the beginning, the middle and the end. Simple, but some maps fail to follow this rule. And as a consequence they are messy, hard to follow, and/or end up in a rage votemap.
The Beginning
I cannot stress this enough. The beginning is the most important part of a map. It is where the players first spawn, until they need to run away to escape. If you do not have a good start, then the map will fail very early, and will be deemed as impossible or annoying by players.
There are many ways to make a beginning. You can have many places where players spawn, and have them converge, or start all at the same time and converge later in the intermediate part. It does not really matter, feel free to choose one. What you must do, is to make sure you follow this set of rules, so that you have a strong start.
-Add more than 72 spawn entities
-Make players escape individually by themselves for about a minimum of 30 seconds before the first mini-survival.
-Make alternative paths, which must not have a maximum difference of 5 seconds.
-No, terrorist filter activated stuff
-Make it easy to follow.
It is very frustratingfor players to not be able to join a team because there are not enough spawn sites. Usually servers have a limit of 64 players. But I have seen some servers (Not zombie servers) which are up to 72. Just add more than 72 spawn sites incase one of them is corrupted. Also ensure to lift them a bit so players do not start stucked!
You must make them run for about 30 seconds, because some servers do not bring the selected zombie back to the spawn zone. The first zombie is chosen no later than 30 seconds, so if you place a mini-survival before that, there is a good (more like bad, for humans) chance that the lead humans will turn into zombies, and the map will culminate in a fail run. As fun as this might sound, this is very frustrating, gives the feeling the map is broken. By making alternative paths, you decrease the chance of all humans being turned into zombies. If you have 3 paths, and 1 is turned into zombies, you would still have 2 human groups for them to survive.
Please no terrorist-human activated stuff. I mean no barriers that will block a team. You might think that you are stopping zombies, but if the zombie has not been chosen, then there is a chance that you are stopping innocent terrorists. Keep the filters for after the first mini-survival.
Make the path easy to follow, people should get an idea of where to turn on the first run! Do not waste their time trying to find a path. More on guidance later.
Worst offenders for a start
-ze_stargate_missions, at the spawning time, it can get very complicated to follow on the first run, and the first rounds are annoying. Most of the time, people spend it been lost. -ze_lotr_helms_deep, the start is buggy, the right side spawn zone, is shorter, and if a zombie is chosen there first, there is a chance it will screw up many people, not to mention that gate will open at the time humans are running.
The Middle Run
This is a simple part of the map, the escape run. Try to make it gentle and nice. Do praise the fastest humans, but without punishing the last human. Keep these points in mind, when planning your map.
-Do not make it too much of anything!
-Make it easy to follow!
-No instant trains/cars/platforms please
-Make alternative paths
-No secret short cuts
-Mini-survivals
-zombie stoppers
-Watch out for camping places
Please, do not make your map all running, or all obstacles, or all boats for that matter. Change it a bit, be creative! Also, make it easy to follow. I find this the most fun part of making a ze map. There are tricks you can use to lead players into a path. Simply make a dirt road on the middle of a grass field. You can try putting nades/health kits/weapons on the way, so when people see them, they will mindlessly go there. Valve uses those in many of their games. Read the developer commentary! Or simply, use arrows and signs.
Try not to make a car/train/platform that starts going after about 2 seconds. The first player will not wait for others. Admins want to play too, they do not want to enforce their rules trying to make your map playable. They actually do not need to do that, there are plenty of other maps to play. Praise the fastest player with a weapon, or maybe he is teleported to a mini-gun on top of a barricade to shoot zombies, (Actually, the mini-gun sounds pretty cool, feel free to make it!), but do not punish the slow players by leaving them on foot, they are the ones, after all, who need a break from running. So give a 10 second wait, or simply have many cars/trains/platforms parting every 5 seconds, or so.
Make more than one path. This will have 2 main good effects. If one group gets infected, then other groups have a chance to survive. Not to mention, that a players computer will have to render less players and will save up some frames per second. When making alternative paths, ensure they are all visible to the players, so that they randomly choose one. If one entrance to an alternative path is closer, then players will tend to enter there more, making the availability of alternative paths useless.
Please no secret short-cuts. Even if you praise a good, keen-eyed player, eventually it will be known by all of the players, making your normal paths useless, not to mention it will unbalance the gameplay of your map greatly.
Mini-survivals, are an important part of a map. It breaks the pace of running/escaping, and gives a chance to humans to fight back and slow players can catch up. There are a couple of points however, that you must follow. Keep them short, so that zombies do not go to the final survival with low hp. And do not place many of them. You want your final survival, to be an intense survival, and if the zombies are already about 1000 hp left, it is not very intense. You could heal zombies for extra challenge for players, like I did in ze_motanuminc. (Details on how I made the healing later).
Zombie stoppers, it is hard to decide how long they should last. You want to give a chance for humans to run after a mini survival, but not a long one, just so that it is from mini survival to another mini survival. You also want to give a chance to zombies, to infect 1 to 3 players on the way. Please do not rely on people walking backwards and shooting as a measure to survival, as its very hard to do and sometimes ineffective to do because of hitboxes/ping/tick. The safest thing you could do, is to find a clan with a zombie escape server, and ask them to test your map, and you change times accordingly your view. If it is a short run to the next survival, maybe 10 seconds, or if it is a long run maybe 15, 20. Do not over do it, as if zombies do not move, then they get bored. Keep your map fun for both parties.
Watch out for camping places. I learnt this the hard way. If you make one path obstacle, then watch out for people who just stay in one unreachable place camping. In ze_ApertureScience, after X time the first player ran through something, then a ladder will appear, and camping players will be pushed. This is to make it easier for zombies to fight against campers. In ze_MotanumInc, players left behind, are teleported to a place they are vulnerable, this does not support camping. Any players who try to camp, will face certain infection. Try forcing the players to move forward. Try to make it look natural too, do not simply make a trigger_push entity. Be creative!
Worst map offenders
-ze_jurassicpark too much running, and people do not wait for jeep. It is frustrating.
-ze_voodoo_island and ze_atix_helicpter too much camping, it can be frustrating for zombies
-ze_blackmesa short cut makes the map quite unbalanced
-ze_deathstar and ze_potc for my likening, the zombie stoppers (specially after mini-survivals) should be longer
The Grand Finale
Valve praises players after long battles with what they call vistas ("Looks" in Spanish). When a player finishes a battle, like in Episode 1, they get to see the destruction of the evil citadel. It rewards players for accomplishing the game. Try to do this. Let the players see the sky, if they have been inside an underground compound. Or see the destruction of a big city they were escaping. There are many things you can do. What you want, is for the players to say to the server admin "Can we go to that cool map, where you see bla-bla-bla explode?". In layman terms give your map a signature. In my ze_aperturescience map, players get cake and see a good destruction of aperture science behind them. In ze_elevator_escape, player see the sky after a long stay in a dark, eastern European facility, in ze_lotr_mount_doom, players see the "Eye" fall apart. It looks cool and it thanks the player for playing your map.
Make your last survival long and offer a challenge to surviving humans, do not make it too hard for humans either. About one minute surviving before the final escape is good enough and long enough. Heal zombies, if they have taken too much damage at some point, but be careful for exploiters. I find that using ontrigger>!activator>addoutput>health 2500> delay 0 is good, and to fire it to only one zombie at the area every second (Use a team filter, to heal only Terrorists/zombies). So zombies cannot relay too much on it. And it is still challenging for humans. Good teamwork will be key, as when some are firing, other reload.
I like to have explosions behind my escapes, so people feel the pressure to escape, and because it looks cool. However, I found in earlier versions of Motanum Inc, and that new players just get confused and frustrated. So, if you plan to do something similar, give time for humans to set up, before the final run begins
Good finale maps
-ze_stargate (missions and the earlier one) challenging for humans, but it is worthed once you win. In missions is cool to escape behind the collapsing tunnel. But maybe give us a chance to see aftermath of it?
-ze_motanuminc it can be hard for both parties. It requires good coordination from humans and persistence from zombies
-ze_elevator escape, you see the sky after being indoors for a long time. and the last survival can be challenging
-ze_deathstar good ending with the starship, I think it could be cooler with explosions behind you
Worst finales
-ze_jurassicpark Many times, zombies do not even finish the run, or finish it too late. And the ending is not very challenging and at times it is boring.
General Tips
Optimize, optimize, optimize.
We, like smooth maps. If you get 100 fps on your map alone, that number could decrease to almost 20, fps, because of loading physics objects, player models, etc. Learn to optimize, there are good tutorials out there. Think twice before placing a physics prop, do you really need it? Are those calculations necessary?
There are two kinds of people
Map exploiters and complete retards! Players will exploit bugs for their benefit, so test your map. Players are complete retards when it comes to escaping, and even sometimes with big signs on the walls they will still get lost (I have seen people get lost in the test chambers of my ze_aperturescience, even though, I put big cake signs to mark the way)
Be creative!
Try to make something that has not been done before. I heard once a guy saying “Wouldn´t it be cool if you could like shoot this helicopter down?" That was my spark for ze_motanuminc, then I heard a guy playing that map that "it would be cool, if you had like 2 boats and one is for zombies and another is for humans" and so, I added it.
Listen to feedback
They might have ideas, and even see stuff you did not see before! Really do listen to it. If they say they hate the map, ask why. If they reply because “its massively gay”, listen no more. If they say because it’s dark, to narrow, to short, etc. Take that into consideration for your next map/version
Compile in NORMAL!
It will make your map look better, and be more optimized! Ze_aperturescience takes 4 minutes to compile in normal (The whole map) and ze_motanuminc takes 3 minutes to compile. They are very big, full of entities maps, with many details and props, it should not take longer than 5 minutes, 7 maximum. If it does, then you might have a leak, or start func_detailing small brushes. Again there are other tutorials in optimization. When I go out spectating, I should see black in the nothingness and a nice all view of the map. I should not see the skybox, or like if there is a nodraw in the nothingness. People when they die, like to get a good view of the map, if they can´t they may not be able to see their error, or plan ahead for next round.
Use propper to make models!
Again there are tutorials on this already. But the basics are, if you have a vehicle of some kind, which is complicated (Like that freaking buggy jeep from jurassic park), take the jeep, and make it into a model (Propper, lets you make brushes into models). Then make a simple brush for func_tracktrain>prop_dynamic model. It is more efficient. Remember, that brushes are heavy. If you have a 50 brushes helicopter, you can transform it into 1 prop_static object, which is more efficient. ze_motanuminc´s boats are models, the moving helicopter is brushes (Could not get it to destroy and work properly as a model) and all other static stuff like turbines, and parts of helicopter, are models.
Use pakrat!
It is annoying seeing those purple checkered stuff, and error models. When you make your final compile, pack the custom models/textures. Then have a friend test the map for missing textures. If he is sure, there are no errors, release the map. You cannot test for missing custom textures/models as you already have them, and even if you did not pack them to the .bsp, you would see them as normal. So ask a buddy, I am sure, he would be happy to take a sneak-pic to your latest creation.
Random Events
This is a new technic I am using lately, but that is used in Left 4 Dead 2 quite often. In L4D the developers noticed that sometimes people just choose one way all the time, when they made about 3 different ways. Simply have a trigger>logic_case>pick_random to choose a random path. This technice will allow for your map to be more different and more exciting. So using this technic you can force players into going through different paths. The nice thing is that your paths do not need to be balanced because there is in reality only one way.
Conclsuion
If I have mentioned your map in a bad way, I’m sorry, but it is my point of view. Think about it, and maybe fix it consider it for your next zombie escape. I know this might arise a bit of discussion, but hopefully, it will make zombie escape maps more fun for both humans and zombies. I am not saying all maps should be exactly this structured, but do keep in mind these key points i mentioned. I came to these conclusions, after making maps for now, over a year, and being a player myself. I know I cannot please everyone with my maps, and there will always be haters, but hopefully, with this tutorial you will please most of the players, or at least many enough so that it gets voted up. As a mapper, I get extremely happy when I see my maps being played on a server, hopefully you guys will get that chance too.