Dungeons:
There are five rarities for dungeons. Each of them have their own threat levels.
Common dungeons(white): the lowest level of dungeons. Most mobs in here are similar to prey found on Earth. Since it is a lower rarity, the loot found in these dungeons are not as valuable, but they do restock more often.
Uncommon dungeons(blue): this rarity of dungeons can house less docile creatures. The loot found in these dungeons are the equivalent of an item from a more expensive store compared to a cheap store. Mobs will only attack you if you interact with them in a violent manner.
Rare dungeons(Silver): We finally get to where the aggro creatures are. Loot found here is hard to find, not because it's hidden. Loot can only be found by defeating mobs. Mobs will guard treasures or have loot on them that drops upon being defeated. Most low level hunters and pseudo hunters are sent here.
Mythic level(gold): The second highest level of dungeon. Loot here is the equivalent of custom made items in the real world. Mobs here will attack anything that enters this dungeon. Most hunters aren't even sent to these dungeons because most of them can't handle the treats in these dungeons.
Legendary dungeons(Platinum): Death is a certainty for anyone entering these dungeons. Not only do the mobs try to kill hunters, but the very terrain itself seeks to destroy all invaders. No one has ever obtained loot here, nor have the mobs here been documented.