The Thrall is a secondary character with its own set of stat enhancing skills and items.
To access the thrall panel click on the helm icon or hotkey (P)
Thralls need to be leveled up using the star system. They can be leveled up using other thrall cards that the player does not want or need. This can be done at the thrall trainer or at the black smith
Click on the equipment bu
Click on the skill bu
Now as players can see, the thrall is a different class to the main character and with so many choices of thrall to use, players have plenty of options. The skill panel for the thrall allows players to add passive skill cards to the thrall. Those are dropped in the dungeons
There is a number of different passives so it pays to think about your thrall and what passives are best suited to it.
The skills can be made using items at the blacksmith whom in in the center of town, click on combine which is 4th down on the list and then thrall card, this will list all the passive skills for the thrall and what items are needed to make the card required
It will show the items required to make each card... unused or unneeded cards can be broken down at the blacksmith by clicking on dismantle which is the 3rd bu