The hedgehog is a ter'angreal that was stolen from the White Tower by Liandrin's Group of Black Sisters.
Appearance[]
The ter'angreal is a wooden carving in the shape of a hedgehog, no bigger than the last knuckle of a man's thumb.[1]
Use[]
Any woman who tried to channel through it went into half a day of peaceful dreamless sleep,[1] and it could be used to trap others as well. However, there was apparently another, much more dangerous, use of it.
It was left by the Black Ajah who fled the White Tower as a trap for Moiraine Sedai in Tear.[2] Faile, who had instead triggered the trap, was captured in Tel'aran'rhiod and her body in the Waking World remained almost lifeless. The hedgehog was broken in Tel'aran'rhiod (in the Wolf Dream) by Perrin Aybara to rescue her.[3]