I have a script that uses OnCollisionEnter and the collision is between two objects.
One is an object that increases in size, that object has a sphere collider, and the other is a sphere that stays the same size, also with a sphere collider.
When the player walks into both objects the player can collide with them, but they can’t collide with themselves for some reason? Is it bug? I’m not sure that it makes sense.
Just colliders arent enough to make the collision be processed, one of the objects involved must have a rigid body. This is the reason that it work with your player but not between themselves
Look at the bottom of this page to see what needs to be present for OnCollisionEnter to happen.
A collider without a Rigidbody is Static (non-moving). They don’t collide with each other because it doesn’t make sense, they’re Static.
This means you’re using the Transform to “move” stuff which isn’t physical movement at all. You use a Rigidbody and use its API to cause movement.