Random number generator with modifiable chance for each value

Dice.cs

using UnityEngine;
using System.Linq;

public abstract class Dice
{
    protected Side[] Sides { get; }

    public Dice(Side[] sides)
    {
        Sides = sides;
    }

    public int Roll()
    {
        var winnerSide = Sides
            .OrderByDescending(side => Random.Range(0, side.chance))
            .First();

        return winnerSide.value;
    }

    public struct Side
    {
        public readonly int value;
        public readonly float chance;

        public Side(int value, float chance)
        {
            this.value = value;
            this.chance = chance;
        }
    }
}

public class GreedDice : Dice
{
    public GreedDice() : base(GetSides()) { }

    private static Side[] GetSides()
    {
        var sideCount = 6;

        var sides = Enumerable.Range(1, sideCount).Select(sideValue => new Side(sideValue, GetChance(sideValue))).ToArray();

        return sides;

        float GetChance(int sideValue)
        {
            var standardSideChance = (float)1 / sideCount;

            return sideValue == 1 || sideValue == sideCount ? standardSideChance * 2 : standardSideChance;
        }
    }
}