This article has been approved and can also be read at the University. - Leif Ericson

For quite some time, ingame Tech trees were believed to be an uneditable, hardcoded part of the game. While they do have several hardcoded behaviors, adding units and researches is a fairly straightforward process, though completely different then adding them to the game itself.

You'll need Advanced Genie Editor and a unit or research to add. There are four subtabs in AGE's Tech Tree tab. You'll need to access three of them in order for changes to work. To begin, select the Tech Tree tab, where the Age subtab should be open. Find the appropriate Age (green), add new item (red), then change the ID to match the unit or research ID (blue).

Age Tab


Buildings work almost exactly the same way:

Building Tab


Additionally, the ordering in these list sets the left-to-right priority for units and researches. When multiple items are in a building, the lower IDs will appear on the left side. This is only within the same list: all units will be farther to the left than any research.


Unit are more complicated, and work a little differently depending on if they are the first/only unit in their line (Villagers, nonelite Huskarls, Battering Rams) or are an upgrade. In either case, the first step is switching to the Unit subtab and adding a new unit (red). As with most edits in AGE, it is highly recommended to copy a similar existing entry rather then create new one from scratch. Once that's done match the new entry's ID to the unit you want (blue). Note that this is the ID in the Main unit tab, not the ID in the list you see here. Also set the Upper Building, (where it is trained) shown in green. Again the ID in the unit list, not in the building subtab. Finally, make sure the age is set properly, (orange) to 1 for a Dark Age unit, 2 for a unit first available in Feudal, 3 for Castle age, and 4 for Imperial Age.



For a unit that is not an upgrade, set the Enabling Research (green) to the research that enables the unit. Leave it as -1 if the unit is availiable without research, like the militia. If it has upgrades, go to the Connected units section, (blue) and add the unit you want to appear directly below it. Further upgrades are not required, hence no paladin here:



For an upgraded unit, Set the Required Research (blue) to the relevant unit upgrade. Alter a slot in Connected items (green) to the preceding unit in the chain. Set the second box (red) to the preceding unit ID and the first (orange) to 2, which represents units rather Ages, buildings, or researches. Finally, set the Connected Units to the next unit in the chain if it exists. If it doesn't, don't put any entries in Connected Units at all.



For researches, add a new research and copy a similar one to it. Set the Research number (green) to the research ID, the Upper building (blue) to the building where the tech is researched, Age and prerequisite upgrades in Connected Items, (black) and subsequent researches in Connected Researches (orange).



Be sure to edit all connected entries for each change you make. Generally, the object just won't show up if you forget one, but some missing changes can cause the game to crash when you view the tech tree. I spent a lot of time learning this the hard way when I added a second upgrade to the Scorpion without adding a Connecting unit to the Heavy Scorpion.


Finally, there a few important limitations to keep in mind when editing the Tech Tree:

·Unique units and techs that appear in the tree for only one civ can only be added to the castle. Otherwise, they will be appear for all civs. To activate this behavior, use researches that are civ specific for the Research ID, Enabling Research, or Required Research.
·You cannot add new buildings without exe editing
·The Dock and Monastery have a hardcoded connection number: If you add new units or techs, older ones will vanish, and if you take any away, lines that go nowhere in particular will appear.
·Units must have no more than one enabling technology to appear correctly. More complicated setups, as in Age of Chivalry, must be accomplished with duplicate units.
·The red X is placed on items disabled by the Technology tree of a civ. Disabling tems with another tech will not cause it to appear.

[This message has been edited by Vardamir (edited 08-08-2017 @ 12:30 PM).]