As well as various extras you can purchase special classes that are only available to those people that unlock them.
The two classes that are available are:
Hermit
This class is available as part of the Jurassic Wars expansion pack, the pack costs 15USD and includes Juratania a savage and forgotten land that has been recently re-discovered.
This land includes tough monsters, lots of new quests, special and unique races such as Raptors, Bone Dragons and Dragon flyers and countless hours of extra content.
The Hermit class eventually leads to the Druid evolution at level 650 and provides the ability to tame plants and insects such as the cool Dragonflyer race.
Salvager
The latest addition the Salvager class is another cool addition to the game that includes the ability to deconstruct items and earn extra money from looting monsters and gathering junk that other classes would not have noticed.
The Salvager leads to the Archaeologist class and along the way gains the ability to find treasure maps, track items and dungeons and unearth mysterious relics.
More information on these two classes is available below.