Welcome to modding in Age of Empires IV!
There are several types of mods you can create using the Age of Empires IV Content Editor, the main tool you will be using to create mod content.
Mods in Age of Empires IV fall into four distinct categories: Crafted Maps, Tuning Packs, Generated Maps, and Game Modes.
Crafted Maps are custom maps you can create for multiplayer matches, skirmishes, or custom games.
These maps can contain terrain, wildlife, resources, units, and similar elements, and can even include scripted events.
Due to the ease of working with Crafted Maps, it is recommend anyone new to modding start with this mod type.
For documentation on making crafted maps, see: Crafted Maps
Tuning Packs modify the statistics of Age of Empires IV units.
Through the use of Tuning Packs you can modify unit cost, speed, toughness, attacks, and almost any other aspect of a unit that affects its use or behavior in-game.
These mods are more technical than Crafted Maps yet still straightforward to create once you get comfortable with the interface.
For documentation on making tuning packs, see: Tuning Packs
Generated Maps are used to create randomly generated maps for skirmishes or multiplayer maps.
These maps aren't really "maps" in the way Crafted Maps are, but sets of data that nudge the random map generator in a specific direction, and will be slightly different each time they are created.
This type of mod is more technical than Crafted Maps or Tuning Packs, and is recommended for experienced modders.
For documentation on making generated maps, see: Generated Maps
Game Modes allow you to re-write the fundamentals of Age of Empires IV, changing victory conditions, game behavior, match dynamics, and other central elements to how the game usually works.
This is the most fundamentally powerful type of mod, allowing you to even create entirely different games within the Age of Empires 4 game engine.
Due to the high level of technical and scripting skills required, Game Modes are recommended for expert modders.
For documentation on creating game modes, see: Game Modes