In this lesson, you will learn how to customize individual instances of a Prefab without breaking the link to the original asset, and how to manage those specific changes.
The Concept of Overrides
When you drag a Prefab into your scene, you are creating an Instance. Usually, you want all instances to behave identically. However, sometimes you need one specific door to be a different color or a specific trap to have a higher damage value. When you modify an instance property in the Inspector, Unity highlights that field in blue. This is a Prefab Override.
Think of the Prefab asset as the "Master Blueprint." When you change a value on an instance, you are effectively placing a "sticky note" over that specific property on the blueprint. Unity keeps track of these sticky notes so that if you decide to change the "Master Blueprint" later (like changing the base speed of all traps), your instance will still respect your custom sticky note for that specific property while updating everything else.
Managing Your Changes
In the Inspector, you will see the Overrides dropdown menu at the top of the Prefab instance. This is your control center:
- Apply All: This takes your "sticky note" (the override) and pushes it back to the original Prefab asset. Now, every single instance in your project will adopt that new value permanently.
- Revert All: This throws the sticky note away, resetting your instance to match the Prefab asset exactly.
If you have a customized object, you can verify which specific properties have been altered by clicking the blue vertical bar next to any modified field.
// Example: If you change the 'damage' value on a specific
// Trap instance in the Inspector, that change is saved as
// an override, keeping the rest of the object synced with
// the prefab's default logic.
public float damage = 10f;
By using overrides, you maintain a "Source of Truth" for your game objects while allowing for the unique variation required for complex level design.
Key Takeaway: Prefab Overrides allow you to customize specific instances while maintaining a link to the base asset, giving you the flexibility to deviate from the blueprint without losing the ability to update your objects globally.