The Prey gamemode we have been working on is probably near beta or at a fully playable beta level. This means that we can try to open it up for people to create new content, with maps being our primary focus right now. As I've probably used too many words, there is a TL;DR at the end with the design ideas condensed. Since it is a new gamemode and it is still being polished, there are no absolutes. We would want you to experiment and explore on your own, trying to come up with new twists over the gameplay mechanics to test whether your ideas work or not. At this early stage, the gamemode is very open to being defined by what specific mappers do, very much like other modes were in the past. Prey obviously borrows from classic 'barricade' based zombie mods, alongside with BaseBuilder styled mods. However, there are specific mechanics unique to Prey, and the way the two aforementioned main inspirations interact together mean that maps built for either of them might not work very well. Indeed, most maps on the server right now are ports from ZombieMod maps. Personally, I don't think those ports are the ones that work best with the mod, though some of them might become a real blast when player population grows and becomes stable. Basic holds The basic gameplay element for Prey is a hold. A hold is nothing more than a space you can defend from the aliens as a marine. The basebuilding aspect of the mod comes into play by placing props which human players can pick up to build their barricades. Generally, you want holds to have from one to three entrances, and have enough props to make up for AT LEAST two lines of cover. I have generally used prop_physics_override as the class for my props, because the solidity model feels more satisfying and the suposed performance losses are negligible. In general, you want your holds to be balanced for both teams. If you feel like you might have too many props, or they might last too long (though, in general, prop HP should be left to the server's plugin, which manages it through a database), you may: Open up a gap for corroders to spit acid into the hold. Create an aditional way of harming players inside the hold (steam? fire?) through I/O. Use ledges that are high enough so that you need to risk walk on the edge to shoot facehuggers. Facehuggers are very small at the moment, so their size might change (to make gameplay more fair) but this principle will still apply. Verticality and openness Prey as a mod favors verticality in maps, that is, having multiple heights and elevation levels. Three of the classes, as of this writing, play with height in a different way than normal CS:GO matches or other mods do. You can fly with a Manta or double-jump with a Facehugger or a Mother Alien. The freedom of movement that comes with the mod means that maps should try to be as open as possible. If you FEEL that you should be able to go somewhere, then you MUST be able to reach that somewhere. Marines can build prop towers to reach a place. Mantas can fly to it. Working with verticality means designing holds with it in mind: a house might have a second floor with a window through which a manta might go. People like secrets Secret areas have always been enjoyable, but some mods make better use of them than others. Mods that are very upbeat and dynamic from round start make secrets harder to pull off well. The same applies with mods that are inherently collectivistic and/or team based. Prey is usually more enjoyable when working as (small) teams, but it doesn't quite fit either of the two categories. Because of that, secrets go well with Prey. Secrets might be either useless gimmicks that add nothing to gameplay or distinct holds with some extra trick to accessing them. When they're of the first kind, you probably have nothing to worry about. The second kind, however, you should carefully balance: you don't want spots where aliens can't get into at all, giving marines win after win once the secret becomes known. Conversely, doing a set of perhaps annoying tasks to get to a secret hold spot that isn't very safe feels pointless. TL;DR: So far, the maps that are enjoyed the most have a good amount of different hold spots. These spaces make use of props (I recommend prop_physics_override) to accomodate the basebuilding aspect with the ZombieMod nature, adding twists like gaps for acid spits, additional I/O or ledges that hide smaller aliens (facehuggers). In general, it is good to remove arbitrary restrictions and make sure you exploit vertical (multi-layered) gameplay as much as you can. Finally, adding some balanced secrets always brings players back into a map, for people that know them can tease the ones who don't, and those will want to discover them.