Scott Wilhelm wrote:
I would make the Gnome a Bard. I think this villain would work best in a highly political campaign. I would pose the Gnome as an apparently friendly NPC who would give the party quests to go on that would, in the big picture, destablilize the political scene, cause evil behavior to run rampant, and force good yeoman farmers to turn to evil patrons to save their farms--borrowing money from Blue Dragons for instance--leading to their eventual enslavement. The party might even be profiting wildly from their adventures, and the upheaval they cause may lead them to even more profitable endeavors.
Say for example, there is a group of Dwarves, the Kalash clan, beset by goblins, and the friendly Gnome Bard tips off the party about a secret formula for a Golem that can be mass-produced cheaply, and self-replicates into 2 golems when destroyed. They are given the name of an especially skilled Dwarven Craftsman, I'd call him Mikial, who knocks together a batch of 47, and over the course of the game, we start to see the whole countryside getting ravaged by the Golems of Kalashnikov...
Say, for example, there is a town that is being plagued by giant ants, and the party comes in to eradicate them. Later we find the ants had a symbiotic relationship with an enormous Black Pudding that procedes to devour the town.
Eventually, the forces of good in your campaign will start to correctly deduce that the party has been responsible for the worst tragedies that have been plaguing the nation, and the party is astounded to be surrounded by a ring of gleaming cavalier paladins, all pointing their lances at them, to bring them to justice. They stand to hear the laundry list of atrocities they committed and never knew they were causing, all inspired by the helpful, little gnome...
Hey man thanks :) that's a pretty awesome IDea