How can i make zerg ai make units like marauders normally if i already gave the larva the ability to make marauders?
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An artist's depiction of an Extended Unit Death
I'm not sure if this is possible with the Data Editor, as AI is handled separately.
Over in the trigger editor, there are actions for the AI you can assign directly. For example, the "AI Advanced - Train" action will tell the AI to train a specific unit (so you could tell them to train marauders). You can also assign a priority to the command if it's something that should be immediate or far down on the to-do list.
Look around at the AI and AI Advanced actions in the triggers. There are several options available to customize your AI. I'm not sure if just telling the AI to train a unit that it is not familiar with will work. Something that is more likely to be successful is getting a larva at random and directly prompting it to become a marauder via the "AI - Issue AI Order" action.