Perhaps the most dreaded and feared abomination to stalk
the forests, the troll berserker symbolizes the rugged
and deadly fighting prowess of the Shattered Bone trolls.
A berserker feels no pain, and is thrice as strong as
the average troll, and seems to possess a limitless amount
of endurance.  When in a rage or bloodlust, they are a 
danger to all around them...even a fellow troll.
Only the most fit of all troll young are taken and trained
to become a part of this special sect of trollish warriors.
They are first trained to endure pain and fatigue beyond
that of the common warrior.  When they are deemed ready,
the eccentric troll alchemists give these brutes all
sorts of mystic brews to chemically enhance their strength,
stamina and speed far beyond what nature had intended.
It is also suggested that the right combination of chemicals
speeds up the rate at which the body heals; this, regeneration,
is perhaps one of the more fascinating traits of the 
troll berserker.
There is a side-effect, however; though the drugs promise
super-natural strength, the imbiber more often than not
succumbs to a mind-altering psychosis that often fills
them with blind rage at the sight of an enemy and blood,
and in extreme cases, causes madness.