ScoreManager.cs

    public GameObject multiplier;
    private float multiScaleRate = 0.005f;
    private int currentMult = 1;
    
    void Update ()
    {
        // Check size of multiplier object and reduce it if required
	    if (multiplier.transform.localScale.x > 1)
	    {
            multiplier.transform.localScale = new Vector3(multiplier.transform.localScale.x - (multiScaleRate * Time.timeScale), multiplier.transform.localScale.y - (multiScaleRate * Time.timeScale));
        }
    }
    
    private void SetMultiplyer(int mult)
    {
        // Don't do anything if multiplyer hasn't changed
        if (mult == currentMult)
        {
            return;
        }

        currentMult = mult;
        multiplier.GetComponent<Text>().text = mult + "x";
        multiplier.transform.localScale = new Vector3(1.5f, 1.5f, 1);
    }