Unity - Simple flickering light source using Light2D.

TorchLight.cs

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Experimental.Rendering.Universal;

public class TorchLight : MonoBehaviour
{
    [Range(1, 100)]
    public int flickerSpeed = 50;

    [SerializeField]
    private float minIntensity = 0.2f;
    [SerializeField]
    private float maxIntensity = 1.0f;
    [SerializeField]
    private float minOuterRadius = 0.5f;
    [SerializeField]
    private float maxOuterRadius = 1.0f;
    private float randIntensity;
    private float randOuterRadius;
    private float lastFlicker;

    public new Light2D light;

    Queue<float> flickerQueue;

    private void Reset()
    {
        flickerQueue.Clear();
        lastFlicker = 0;
    }

    private void Start()
    {
        flickerQueue = new Queue<float>(flickerSpeed);

        if (light == null)
        {
            light = GetComponent<Light2D>();
        }
    }

    private void FixedUpdate()
    {
        if (light == null)
        {
            return;
        }

        while (flickerQueue.Count >= flickerSpeed)
        {
            lastFlicker -= flickerQueue.Dequeue();
        }

        randIntensity = Random.Range(minIntensity, maxIntensity);
        flickerQueue.Enqueue(randIntensity);
        lastFlicker += randIntensity;

        randOuterRadius = Random.Range(minOuterRadius, maxOuterRadius);
        flickerQueue.Enqueue(randOuterRadius);
        lastFlicker += randOuterRadius;

        light.intensity = lastFlicker / flickerQueue.Count;
        light.pointLightOuterRadius = lastFlicker / flickerQueue.Count;
    }
}