What is the easiest way to deep copy a list of gameObjects?

Ok, if I am understanding your logic, you have:

- A list of GameObjects B , each with a ScriptData component attached to them
- A GameObject combatUnit , which has a UnitSegmentList component attached to it
- A function in UnitSegmentList called SetValues() that takes in one parameter of type List<ScriptData>

You want to send all of the ScriptData information into the SetValues() function of the combatUnit in a way that any modifications to the list data in combatUnit does not in any way affect the data already stored in B

This is a rather difficult problem, primarily because ScriptData inherits from MonoBehaviour , which means that you can't create a copy of an instance of ScriptData without attaching it to a GameObject, and you would need to create a copy of every GameObject in B and keep them in scene to achieve your desired results on your current setup.

An easy solution would be to store any information in ScriptData in a single Dictionary/Array/HashTable, depending on the nature of the data that needs to be passed into combatUnit . For example, if you had a list of stats:

 public class ScriptData : MonoBehaviour
 {
      public int[] stats;
     
      // whatever else is in the class
 }

You could then pass in clones of the stats variables into list A

 List<int[]> A = new List<int[]>();
 foreach (GameObject x in B)
 {
     A.Add(x.GetComponent<ScriptData>().stats.Clone());
 }
 GameObject combatUnit = Instantiate(unit);
 combatUnit.GetComponent<UnitSegmentList>().SetValues(A);

In this way, any changes made to combatUnit will not be reflected in B

This worked for me:

 var returnData = JsonUtility.FromJson<LevelWaveData>(JsonUtility.ToJson(data));