The following document is the work of Tyson Green, Bungie's Multiplayer Lead on Halo 3. Enjoy part 2 of the Forge Trilogy. For Part 1, "Forge Basics" click here.
To return to Halo 3 How-to click here

Advanced Forgery

On the surface, the Forge is pretty straight forward. Create fusion coil, hurl at friend, repeat ad infinitum. However, there are some other things that you may choose to make yourself aware of if you wish to master your tools.

Inventory and Budget

The number of objects you can place in the Forge is ultimately limited by two things: Inventory, which is the number of a specific object that you can place, and Budget, which is an overall total that keeps things in check.

There’s actually a third limit that kicks in when you’ve got a whole heck of a lot of objects on the map, but really, you need to be looking for trouble to bump into that one. The Forge will just squawk at you and give you a polite error message if you try to go above it. Don’t bother, it’s not that spectacular.

Inventory

Inventory is tracked per object type. Think of it as the limit for that object type—no more than that number of those objects can be placed on the map, or allowed to spawn on the map.

The Inventory is shown to the left of the object name in the creation palette. That number tells you how many more objects of that type can be placed on the map. If that number is 0, you may place no more.

One important note: in addition to the objects placed on the map, the Inventory counts objects which could spawn in later. For example, if a single Spartan Laser is placed in the middle of Valhalla, but the maximum respawn quota for Spartan Lasers is 3, then the Inventory counts 3 Lasers as having been placed. Don’t freak out, there’s more on this later.

Budget

Budget is an overall limit on the objects placed on the map. A Warthog is more expensive to have on a map than a fusion coil. More expensive than several fusion coils, in fact. The Budget is what reflects this.

In your bottom right corner is a little meter, and a number. This is your remaining Budget. The number is the amount of Budget you have left to spend, and the bar fills up as you spend it. If that number is $0, you won’t be able to place more objects.

In the object creation palette, the cost of an object is listed to the right of its name, as a dollar figure. No, the dollar amount isn’t how much will be charged to your credit card if you place one such object. What would we do with such wealth? Instead, it is the amount that will be deducted from your remaining Budget if you place such an object.

Note: as with Inventory, the Budget counts not just the objects placed on map, but also the objects that could spawn in later. More on this later.

Object Spawning

Most objects that you can edit in the Forge can be told to respawn if some evil should befall them. The system that manages this (colorfully called “The Candy Monitor” by our engineers) can be complex, but is worth understanding.

Respawn Timer

When an object is disturbed, it starts counting down a hidden respawn timer. Objects are sensitive things, and consider themselves disturbed if they are moved, picked up, or destroyed.

Once this timer counts down to zero, the object says “hey, I want to respawn now”. But before it does, there is a check to make sure there is not already too many objects of that same type on the map. This is where the quota, described below, comes in. If there are too many objects waiting, then the object waits quietly until there is room before it respawns.

The respawn timer usually defaults to 30 seconds, but this is a property that may be set per object, as described below.



Respawn Quotas

OK, stay calm. This part will seem a little complex, but its really pretty easy.

All object types have a quota. That is, a maximum number of them that can be on the map, and also a minimum number.
When an object wants to respawn, it makes sure that doing so would not result in more objects of that type than the maximum allowed. For example, this is how you can make sure that no more than one Shotgun is on the map at a time, but still place three locations around the map where it could spawn at.

Likewise, a minimum number can be set, in which case objects will respawn immediately if fewer than this number are on the map. For example, we like to set minimum counts on Mongooses, to make sure they’re always available.

To edit the quotas, you can select the type of object in the creation palette, and press X to bring up the summary. This screen tells you how many objects of that type are on the map, what your minimum and maximums are, and also how much of your Budget is being spent by objects of this type. Only the “Run-Time Minimum” and “Run-Time Maximum” can be edited here, the other numbers are just for reference.

Remember: the Budget counts the “Run-Time Maximum” when adding up the cost. You might only place one Sniper Rifle on the map, but if your maximum is set higher than that, a new Sniper Rifle could spawn in.

Is that all clear? If not, don’t worry about it—the Forge always sets the minimum and maximum to safe default values, so you’ll never have to bother with this if you don’t want to.

Object Properties

Almost every object placed on the map has a few properties specific to itself that you can edit.
To do so, place your crosshair on an object. Then press X. This brings up an Item Properties window which contains a list of properties to edit.
This list isn’t always the same—a weapon has different properties than a vehicle, or from a piece of scenery. But there are some common ones:
-    Respawn Rate: This controls how many seconds it takes for an object to respawn. You can use a very low number to make an object respawn quickly, or a very high one to make it less common. You can even tell it to never respawn, in case you want something that only shows up at the start of a round.
-    Place At Start: This controls whether the object starts on the map, or if it spawns in later. If you set this to No, then the object will not be there when the game starts, but its respawn timer will start counting right away, so it will appear after a delay.
-    Symmetry: This cryptic option controls which types of games the object appears in. A Symmetric gametype is generally one where both sides are equals, like Slayer or Multi Flag CTF. An Asymmetric gametype is the opposite, where the sides have different goals, like One Flag CTF or Territories. Clever use of this property will let you set up a map that plays great for Multi Flag CTF, but also works well for One Flag CTF.

Forge Options

Like Custom Games, the Forge does have a few options that you can set up in the pregame lobby. As with custom game options, you access these by pressing X in the lobby.

First, the bad news. That option at the top, the one called “Allow Editing”? In theory, this option would let you restrict editing to the Party Leader, and prevent everyone else from editing. In practice, ah… ahem… well, not so much. That’s what we call a “feature”. It’s like how sometimes, when a plane lands, the tires blow up. Halo 3 is that plane. This was one of those tires.

But the good news is that the other options work smashingly. The Editor and Player Traits are pretty straightforward, and offer a list of traits that you can apply to players in both Editor and Player modes. So if you’d like to go about your editing duties while your test subjects shoot lasers at you, you can tweak those Editor traits to make yourself invulnerable, or invisible.

And the Respawn Time option should be pretty self explanatory. It’s really only there in case you want to get really serious about playing serious games in the Forge, and three second respawns won’t cut it anymore.