I once ran a Dragonstorm campaign, where the players’ characters were given the responsibility to create a hidden refuge in this valley high in the mountains. Part of that involved getting a trusted group of people to come to the valley to help protect it. The players wanted to go out recruiting but I had other plans. Some time in the past, the characters helped out a nomadic tribe by curing it of a very nasty magical plague, so I had the tribe’s wolf totem spirit order the tribe to come and take up residence in the valley. All that gave me a number of new potential NPCs to work with, and I took advantage of it almost immediately.
Dragonstorm is an RPG based on shapeshifters: dragon shapeshifters, werewolf shapeshifters, etc. Each type of shapeshifter has certain abilities because of their shifter blood. Shapeshifters are also hated by the general populace, because of propaganda, and hunted and feared, as well: hence the necessity of the hidden refuge. I decided to make one of the wolf tribe a shapeshifter, but I didn’t make it easy for the NPC: instead of being a werewolf shifter, which would honor the tribe’s totem, she was instead a dragon shapeshifter. She did not take the notion very well, feeling that the tribe’s totem had abandoned her.
All that came to a head when she was arguing with her betrothed. The players’ characters were called in, and were told about the argument: the argument became more and more heated until finally the female shapeshifter glared at her betrothed, who fell unconscious to the ground. The shapeshifter wailed that she killed her betrothed and fled into the night.
The players all facepalmed.
Dragon shapeshifters have the inherent ability to entrance others into a sound sleep through eye contact, and it was very obvious that a) she had done that, and b) no one ever explained that part of being a dragon shapeshifter to her. So, to rescue a new and valued shapeshifter, they had to follow her trail to an unclean area of the valley, where warped spirits were tormenting her through her self-doubts and fears and guilty conscience. They rescued her, of course, and she would eventually abandon the tribe’s ways and become a fervent member of the Valarans, the protective order of shapeshifters the player characters were all members of.