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(1) Never Let Your Player-Characters Be Best At Anything. Player-characters like to be considered experts in their fields, and it’s your job to make sure they understand that they’re really not. Always have an NPC around who’s better at the PCs’ Skills and professions. If you have both a PC and an NPC available to perform a task, make sure the NPC gets to do it. When your heroes are overwhelmed by enemies, have your NPCs save them. Every time. And don’t forget the experience factor; as your heroes get more experienced, make sure that the common grunt enemy gets tougher, too. That way the PCs will never get cocky. — How to Ruin Your Campaign (Champions IV)