Most of the information here is for Warzone 3.1 and above.
Challenge Games
Challenges are predefined game set-ups for Skirmish games that can be access via the Challenges menu.
What are Challenge games?
A challenge is basically a skirmish game with pre-defined settings.
At it's most basic level, a challenge will define:
The map to use (either a custom map or any existing map)
Starting position of human player
Which AIs to use, and their starting positions
However, more advanced settings can also be defined:
Alliance mode, and which teams/alliances players are in
AI difficulty levels
Base type
Power level
Scavengers
etc.
In fact, the Challenge can define any of the settings found on the Skirmish Game Screen and Players Panel, and even lock those settings so the player can't alter them.
How do I install a Challenge?
Well, it depends on the way the add-on was developed. First, locate your Config folder, and then follow these guidelines:
Most challenge games are quite basic:
/maps – add-on filename starts with "Nc-" (where N will be a number between 2 and 10) and ends in ".wz"
/challenges – add-on filename ends in ".ini" or ".wz"
If those don't work, try:
/mods/autoload – more advanced Challenges (eg. that contain their own map or AIs) go here
The person who made the challenge will usually say where to install it – if not, ask them to!
How do I play an installed Challenge?
Challenge games are always accessed from the Single Player Menu → Challenges screen.
If you've installed a challenge but don't see it listed on that screen, the chances are you've installed it to the wrong place (try one of the other folders listed earlier).
How do I make a Challenge game?
Well, that depends on what version of Warzone you're working with and how advanced you want the challenge to be!
Warzone 2.3.x – Undocumented, so take a look at an existing challenge to see if that helps?
Warzone 3.1 – see: <challenge>.ini 3.1
Warzone 3.2 – you can use a 3.1 style .ini file, or a newer format (which isn't formalised yet)
If your challenge is basic, all you need is the .ini file. If you want to include it with one of your maps, take a look at NoQ's challenge maps.
Examples
One of the best examples of an advanced challenge is NoQ's "The Paradigm" challenge, in which the player takes on the role of a New Paradigm base commander that's under heavy attack by The Project and their close allies, The Venture.
Not only does the challenge have a custom-made map, but it also has custom versions of the NullBot AI, one of which has been converted to create a scavenger ally.