Bone Pillar

A pillar of living dragon skulls that have spent their whole posthumous lives trying to achieve a delicate balancing act. A bone pillar cannot be such unless there is at least one dragon skull on top of another, but there is no limit past that, and natural philosophers have reported seeing pillars made up of hundreds of jaw-jittering dragon skulls. Some pillars are very particular about orientation, and have each head alternate in direction (left/right) or face the same way; others are lax about head pointage, and will permit all personal expression.

Once a bone pillar has balanced itself, it can wait years, even millennia, for a hero to arrive. When this happens, the pillar will eject a barrage of flames from its mouths at said hero. It is a mystery as to why bone pillars are so against heroes, or how they can maintain such a goal so steadfastly.

Most bone pillars do not survive more than three seconds against heroes. In reaction to this, some pillars with evolved brains (the cause for this is unknown, as dragon skulls lack brains) balance near deep pits so that their flames will knock heroes into the abysses. This works a little better, but the success rate still isn't above 30%.

A rare variant of bone pillars acts independently. These tend to live diagonally on staircases, accompanied by large, spiked iron balls. These bone pillars are so dedicated to the cause of killing heroes that the elaborate trap only works if a hero dispatches the bone pillar, thus allowing the spiked ball to tumble downward. A spiked ball usually only deals small damage to the hero; however, if the hero is adequately stupid and a bungler of spatial judgment, they will be continuously attacked by the bouncing spiked ball until death.

Heroes will often walk around the spiked ball if it drops — or, if they are having a moment of bravado, will leap over it. Daring heroes attack the spiked ball 9,999 times until it is destroyed.