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Working With The Spawn Engine

Quite a bit of information has been provided to forgers by Bungie on how the spawn engine functions, even so much as to explain some of the under the hood mechanics that are involved. And despite many maps that demonstrate sheer talent in design, a number of forgers continue to demonstrate a basic lack of understanding on how the tools for the spawn engine work. And some continue to use the various Respawn Zones (Weak, Anti, and Strong) to work against the spawn engine rather than with it.

The purpose of my tutorials on spawning in Halo: Reach is to teach in detail and great depth how the spawn engine functions and to a degree how it works under the hood - not to replace what Bungie gave us, but to provide a perspective with greater depth so that it all makes more sense and to offer greater clarity. I took what we were given by JonnyOThan in the way of his spawning articles (which were skeletal at best) along with the many posts he made to clarify how it all works and answering our questions, and combined all of these into the tutorials here at Forging Reach.

This insight provides a forger with a better comprehension of what happens as they utilize Respawn Zones and Respawn Points in their forge works. When they lay down a Respawn Zone or Respawn Point, they can know with certainty how the spawning behavior will work. In fact, one can forge through a map and describe its spawning behavior far more accurately than by testing it over and over again.[1]

This is because testing a map yields a single data point, which in and of itself does not describe how the spawn engine works. It only demonstrates a single case study. Many data points do not describe how the spawn engine works. They only demonstrate multiple case studies. But no matter how many case studies you compile into a collection for a report, you can never say you covered every possible scenario. That simply cannot happen on a game system as complex and vast as Halo: Reach.

But by examining the spawn layout for a map and having a complete understanding of how the components function under the various game types, one can make some conclusions on what one will see - every time. One can definitively claim how the spawning will unfold as the game progresses with each variant scenario.

This last point is absolutely critical. Each variant scenario that one can think of can be analyzed from looking at the spawn layout alone. The results can be determined analytically and changes can be made to the map prior to game play. Testing is not used to determine how to establish spawn layout, but to verify that there are no unexpected behaviors - to verify that our understanding of how to use the spawning components is correct. This may seem strange to people, so let me say it another way.

We have a model on how the spawn engine works presented to us by Bungie and I tried to describe that model in excruciating detail here in these articles. When we test our maps, we assume that the model we have presented to us is correct 100% of the time. Testing helps us find examples where this assumption of ours breaks down. When we find an unexpected behavior, we must classify it as one of two cases.

Either (1) we uncovered a mistake in our use of the Respawn Zones or Respawn Points, or (2) we found a behavior that contradicts official information from the game publisher. In the first case, we work to identify our mistake and then fix it. In the second case, we notify the publisher for comment and clarification. Either the problem is a bug in their spawn engine, or the problem is a behavior that they intended and that they did not document correctly. Usually it is just a bug we uncovered.  And we need to notify the publisher so that they can log it into their bug tracking system and prioritize fixing it. It simply won't get fixed any other way, folks.

When I forge through some maps, I regularly see maps that use Weak Respawn Zones and Anti Respawn Zones. But ask yourself, how many times does Bungie use them on their maps? Most maps don't use either of these.[2] That should say something right there.

Because they impose weights on Respawn Points that alter the selection of Respawn Points, one has to consider very carefully when using either of these zones. In fact, the Weak Respawn Zone is really the last type I would consider using.

I have seen maps that use Weak Respawn Zones over some Respawn Points, but not others. Objective test reports (from others not connected with the map) have included comments, like, "We saw someone spawn over and over again at one location on the map." This is because the Weak Respawn Zone is raising the weight on those few Respawn Points, making them higher than any others, even though the spawn engine tends to assign a very small random value to each so that the spawning appears random overall. In other words, a weak Respawn Zone over 10 percent of the Respawn Points will appear to heavily favor those few, leading to a generally undesirable spawning experience.

Still other maps use Weak Respawn Zones in layers without a Respawn Zone. There are two conclusions we can draw from these maps. First, the forger doesn't understand that the proper tool to limit where a team can spawn is the Respawn Zone, not the Weak Respawn Zone. Second, the forger does not understand that Weak Respawn Zones are documented and confirmed by tests not to combine their weights outside of a Respawn Zone. In other words, the way that the zones are laid out on the map indicate that the forger doesn't have the proper understanding of how to use the spawning tools, or how those tools will behave at game time.

Such maps have two negative spawning behaviors that must be considered. First, given death influencers positioned at the right places on the map, it would be possible in nearly every case to force a player to spawn at their enemy's base. For objective games, this is very bad. The point being that the Weak Respawn Zone does not limit a team to those zones. Second, the application of a Weak Respawn Zone alters the spawn engine's selection heavily, and in many cases adversely.

Here is the point of this article. We as forgers need to quit making spawning so complicated. We need to look at how Bungie intended the Respawn Zones of various types to be used. One good indication is their materials, which I have tried to clarify and make more intuitive through these articles. Another is just looking at Bungie maps. Ask yourself why do they generally always divide a map in half with Respawn Zones and not use Weak Respawn Zones? With that question in the back of your mind, study the spawning model that these articles present. Then let the spawn engine do as much of the work for you as it can. Let it decide which Respawn Point to use rather than throw weights on them by applying Weak Respawn Zones everywhere. Don't tell the spawn engine what the weights should be, but let it decide based upon the game dynamics alone. Define only the halves of the map that you want a team to spawn on, and nothing more.

In essence, work with the spawn engine, not against it!

Those that play your maps will thank you for it.


[1] I highly recommend that those who regularly test maps for others, such as the Testers' Guild at Forge Hub, begin their testing with an analytical report on the spawn layout for each map. This would be really good feedback for the forgers, and can be used to verify results that they observe during testing.

[2] It may be there are no maps published by Bungie that use Weak Respawn Zones. But because I have not taken the time to verify this claim, I cannot make it. All I can say is that I have never seen a Bungie published map that uses a Weak Respawn Zone.