- Banish someone.
The ancients invented this one, which figures large from the Bible (God throws Satan out of Heaven) to modern tales (troublesome kid gets sent to boarding school, dysfunctional narcissist gets kicked off the island).
What’s so great about banishing a character? We know he’s still out there. The malefactor broods on his punishment, grinds his axe and plans his revenge.
If you use an omniscient narrator or multiple-character POVs, you can flip back and forth from the banished to the peacefully complacent tribe, ratcheting up the tension by contrasting what everybody’s doing and thinking.