There was a kingdom, as there always is. Well this Kingdom like many others before it was overridden by a blight called the 'Maddening'. A plague of the mind. It infects the soul and body. Until the host is nothing but a 'Husk' a type of monster with little to no physical form due to being formed of thoughts.
In order to combat this, the kingdom made three forces:
The first to protect the kingdom itself from the Husks.
The second to attempt to slow the progression of the Maddening.
The last to try destroying the Maddening for good using an ancient relic.
Now there is a few problems with the last method:
1. It requires base material from the core of the Maddening itself which resides in the middle of a corrupted Forest.
2. The relic is damaged, and thus can only allow roughly seven people to enter and actually do damage to the core of the Maddening.