A Pixie Impaler is a dangerous Fae device.
It is a small orb that produces numerous spikes when squeezed. Trick keeps one among his possessions.
The Spriggan was identified as a Pixie. It is reasonable to assume that the Pixie Impaler is held in the hand and when you shake the hand of a pixie, the impaler stops the pixie from being able to trigger its power.