Mobs can be easily distinguished from the NPCs seen in towns from how they interact with characters: they cannot be talked to (although they can talk themselves in less common cases), are often hostile to all characters, and will attack when a character comes into range. Mobs of the same kind may share the same name with each other, and have a red hit point bar above their heads (compared to a character's green).
Aside from the common mobs, there are mobs which have a different-colored name, an additional prefix to their name, and a corresponding aura surrounding them. Depending on the color of the aura, these rarer mobs may have more defense, have a higher super armor, or can attack with higher damage. To date, these prefixes include Destructive, Durable, Regenerating, Wilful, Agile and Aggressive.
In Anu Arendel dungeons, Champion monsters can be seen and all but one of these will aid players in battle in different ways when defeated. These include Regenerating (provides healing), Cursing (sucks monsters towards it), Agile (provides move/action speed boost), Raging (provides cooltime reduction, move/action speed boost), Quiet(provides Super Armour) and Fatal (deals heavy damage to nearby enemies).