Dice Roller used to determine which side of a dice has been rolled. Generic implementation capable of working for any number of sided object.

Dice.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

// Written as part of World of Zero
// Video available here: https://youtu.be/hmDF9PvMDVw
public class Dice : MonoBehaviour
{
    public SideResults selectedResult;
    public int selectedVector;
    // Note: the size of the vectorValues and vectorPoints should be the same.
    public SideResults[] vectorValues;
    public Vector3[] vectorPoints; // These vectors should be normalized. Might be worth adding a task to Start to ensure they are normalized.

    // Use this for initialization
    void Start () {
		
	}
	
	// Update is called once per frame
	void Update ()
	{
	    float bestDot = -1;
        for(int i = 0; i < vectorPoints.Length; ++i)
        {
            var valueVector = vectorPoints[i];
            // Each side vector is in local object space. We need them in world space for our calculation.
	        var worldSpaceValueVector = this.transform.localToWorldMatrix.MultiplyVector(valueVector);
            // Mathf.Arccos of the dot product can be used to get the angle of difference. You can use this to check for a tilt (perhaps requiring a reroll)
            float dot = Vector3.Dot(worldSpaceValueVector, Vector3.up);
            if (dot > bestDot)
            {
                // The vector with the greatest dot product is the vector in the most "up" direction. This is the current face selected.
                bestDot = dot;
                selectedVector = i;
            }
        }

	    selectedResult = vectorValues[selectedVector];
	}

    void OnDrawGizmos()
    {
        Gizmos.color = Color.red;
        foreach (var valueVector in vectorPoints)
        {
            var worldSpaceValueVector = this.transform.localToWorldMatrix.MultiplyVector(valueVector);
            Gizmos.DrawLine(this.transform.position, this.transform.position + worldSpaceValueVector);
        }
    }
}

// Enum for storing the potential results.
public enum SideResults
{
    Red,
    Green,
    White,
    Black,
    Yellow,
    Purple
}