Quaternion rotation = Quaternion.Euler(0, 90, 0); // creates a rotation quaternion that rotates 90 degrees around the y-axis Vector3 originalVector = Vector3.forward; // creates a forward-facing vector Vector3 rotatedVector = rotation * originalVector; // applies the rotation to the vectorIn this example, we create a quaternion that represents a 90-degree rotation around the y-axis. We then create a vector that is facing forward. Finally, we apply the rotation to the vector using the `*` operator and store the result in `rotatedVector`. Package library: The Quaternion class is part of the System.Numerics package library, which provides various numeric types and mathematical functions for complex number operations.