mob levels

I think that mobs should have randomized levels, boss monsters would always have the same level (maybe a respawned ender dragon is a lower level idunno) bosses would obviously be higher levels, mob spawners would also produce higher levels than usual, mobs spawned due to low light levels would have low levels, normally these levels would either do nothing or possibly change the XP they drop I'm not sure but in hardcore mode higher levels means higher attack and health maybe there is an enchantment only available through archaeology that increases your damage to higher level mobs, or your movement speed when higher level mobs are nearby. This doesn't need to be added but it could make hardcore mode and PVP more challenging.