Instantiating prefab causes existing instances to change values

Questions & Answers
1

I want to instantiate obstacles so I have a controller to instantiate from a prefab over time, that is assigned through a variable. I instantiate the prefab like so (Instantiation over time works fine)

            Transform t = spawnX; // Transform to hold the x position of the spawn point
            Vector3 v3 = t.position;
            v3.y = Random.Range(minHeight, maxHeight); // Random y position
            t.position = v3; // Get the random spawn point

            // Instantiate the prefab
            Instantiate(obstaclePrefab, v3, Quaternion.identity, t);

Again everything is working fine, except that when one instance is created, all already existing instances update their y-Position which was randomly created to the one of the new instance. Why is that?

2

You seem to parent the instance to the object transform “t” with your Instantiate call, so changing t will affect every children.