var money = 100; // "100" is present in RAM now (as four-byte integer value). Cheat apps can find, filter and replace it since it was declared.
money += 20; // Cheat apps can scan RAM for "120" values, filter them and discover the RAM address of our "money" variable.
Debug.Log(money); // We expect to see "120" in console. But cheat apps can deceive us!
ProtectedInt experience = 500; // four XOR-encrypted bytes are present in RAM now. Cheat apps can't find our value in RAM.
experience += 100;
Debug.Log(experience); // We can see "600" in console;
Debug.Log(JsonUtility.ToJson(experience)); // We can see four XOR-encrypted bytes here: {"_":[96,96,102,53]}. Our "experience" is hidden.

#define NEWTONSOFT_JSON
using System;
using UnityEngine;
#if NEWTONSOFT_JSON
using Newtonsoft.Json;
#endif
namespace Assets
{
    [Serializable]
    public class ProtectedInt : Protected
    {
        #if NEWTONSOFT_JSON
        [JsonConstructor]
        #endif
        private ProtectedInt()
        {
        }
        protected ProtectedInt(byte[] bytes) : base(bytes)
        {
        }
        public static implicit operator ProtectedInt(int value)
        {
            return new ProtectedInt(BitConverter.GetBytes(value));
        }
        public static implicit operator int(ProtectedInt value) => value == null ? 0 : BitConverter.ToInt32(value.DecodedBytes, 0);
        public override string ToString()
        {
            return ((int) this).ToString();
        }
    }
    [Serializable]
    public class ProtectedLong : Protected
    {
        #if NEWTONSOFT_JSON
        [JsonConstructor]
        #endif
        private ProtectedLong()
        {
        }
        protected ProtectedLong(byte[] bytes) : base(bytes)
        {
        }
        public static implicit operator ProtectedLong(int value)
        {
            return new ProtectedLong(BitConverter.GetBytes(value));
        }
        public static implicit operator long(ProtectedLong value) => value == null ? 0 : BitConverter.ToInt64(value.DecodedBytes, 0);
        public override string ToString()
        {
            return ((long) this).ToString();
        }
    }
    [Serializable]
    public class ProtectedFloat : Protected
    {
        #if NEWTONSOFT_JSON
        [JsonConstructor]
        #endif
        private ProtectedFloat()
        {
        }
        protected ProtectedFloat(byte[] bytes) : base(bytes)
        {
        }
        public static implicit operator ProtectedFloat(int value)
        {
            return new ProtectedFloat(BitConverter.GetBytes(value));
        }
        public static implicit operator float(ProtectedFloat value) => value == null ? 0 : BitConverter.ToSingle(value.DecodedBytes, 0);
        public override string ToString()
        {
            return ((float) this).ToString(System.Globalization.CultureInfo.InvariantCulture);
        }
    }
    public abstract class Protected
    {
        #if NEWTONSOFT_JSON
        [JsonProperty]
        #endif
        [SerializeField]
        private byte[] _;
        private static readonly byte[] Key = System.Text.Encoding.UTF8.GetBytes("8bf5b15ffef1f485f673ceb874fd6ef0");
        protected Protected()
        {
        }
        protected Protected(byte[] bytes)
        {
            _ = Encode(bytes);
        }
        private static byte[] Encode(byte[] bytes)
        {
            var encoded = new byte[bytes.Length];
            for (var i = 0; i < bytes.Length; i++)
            {
                encoded[i] = (byte) (bytes[i] ^ Key[i % Key.Length]);
            }
            return encoded;
        }
        protected byte[] DecodedBytes
        {
            get
            {
                var decoded = new byte[_.Length];
                for (var i = 0; i < decoded.Length; i++)
                {
                    decoded[i] = (byte) (_[i] ^ Key[i % Key.Length]);
                }
                return decoded;
            }
        }
    }
}