I believe spite can be an excellent motivator. But unchecked fury? That rarely leads to anything more than a big mess.
When demonic influence corrupts the leadership of a people or an organization, the leaders might embrace abyssal magic to make tanarukks, using these ferocious warriors to bolster their followers' strength.
The demon lord Baphomet|MPMM gladly shares the secret of creating tanarukks with those who entreat him for power; the cult of Gruumsh has also mastered a ritual for this purpose, and bestows it on those deemed worthy. Whatever process is used corrupts the subject, transforming them into a vicious Fiend.
Although tanarukks are valued as fearsome fighters, they are a threat to their allies off the battlefield. When not in combat, a tanarukk is destructive and volatile and is usually kept imprisoned by its allies. If unrestrained, a free tanarukk embarks on a rampage, attempting to take over by force. Most such coups fail but are costly nonetheless. If a tanarukk does seize the leadership of a group, reckless raiding or even war is the course they inevitably choose.
When demonic corruption taints a tribe's leadership, orcs might turn to abyssal magic to make tanarukks. Evil humans who control orcs also use such power to bolster their followers' strength.
The demon lord Baphomet gladly shares the secret of creating tanarukks with those who entreat him for power. The process corrupts an unborn orc of the tribe, transforming it at birth into a creature much more savage than an orc.
Although tanarukks are fearsome fighters, they are a threat to their allies off the battlefield. Within the tribe's lair, a tanarukk is destructive and volatile, and best kept imprisoned. Sooner or later, a free tanarukk rampages through the tribe, attempting to take over by force. Most such coups fail, but at great cost to the tribe. If a tanarukk does seize the leadership of a tribe, reckless war is the course it inevitably chooses.
If a tanarukk manages to breed, its blood taints numerous subsequent generations, so its female descendants randomly produce tanarukks. Rather than risk raising a natural-born tanarukk, most tribes slay such abominations.
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