First of all, I love Kobolds, they're my favorite monster to run for low-level adventures. Ok here are some of my favorite Kobold traps:
*The kobolds have discovered a pit trap in their dungeon that they can reset. The have placed semi obvious signs of a pit trap just in front of the other one. Floor coverings, grooves carved to simulate the edge of the trapdoor, etc. All of these are put there to fool the players into thinking there is a trap there. The players leap over the kobolds poorly designed, albeit fake, trap only to find themselves landing on the real one on the other side.
* Wandering down a long hallway the players come upon a small bucket upside down off to the side of the hallway. The players find upon picking it up that a weasel or rat is trapped underneath it. The creature takes off down the hallway, ringing a little bell that is tied around it's neck and snapping a line attached to a couple of bags of flower. The flower falls creating a flour cloud throughout the hallway. If the players, rightfully suspecting a fire trap, charge down the hallway to "safety." Two kobolds have perched above the room's entrance holding buckets of scorpions ready to pour them onto whoever comes through. If the players hesitate, one of the kobolds hurls an Alch Fire flask in and ignites the flower cloud.
thanks goes out to my friend Des for that one.
*The players come upon a section of hallway where small holes have been cut into both walls on either side. If the rogue, rightfully suspecting a trap, searches the area he finds a cleverly hidden trigger and easily "disarms" it. The trigger is actually a fake one put there to give adventurers a false sense of security. Once they galantly stride down the hallway, a bunch of kobolds on the other sides of both walls begin jabbing spears through the holes.
...Jonas gets the credit for that one.
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