Darkmind (3.5e Template)
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A splinter-only parasite. These worms have existed as long as the splinters have, maybe even longer. These small, purple worms often hang around in the hives that splinters construct, and when they find their way into the splinter's body, they enhance it greatly at the cost of the splinter's 'willpower'. The Darkmind worm is intelligent to a limit and passes that onto the splinter it inhabits, as well as granting the chitin of that splinter extra strength against blunt trauma.
Creating a Darkmind
This is an acquired template that can only be added to splinters.
The base creature gains DR 5/Bludgeoning or Piercing due to the toughening of the chitin.
The Darkmind worm gives the splinter a feral cunning and a intelligence score, allowing it to take feats and skills. +4 Strength, +4 Constitution, and +2 Int.
The splinter's alignment changes to Chaotic Evil, as the worms are self-serving and stir up the hive to begin raids and attacks.