Killing pit
From Tardis Wiki, the free Doctor Who reference
A killing pit was used by the Tribe of the Three Valleys to catch animals such as pigs. They were several metres deep and the bottom was lined with spikes. Aerack and Puran were digging a killing pit before they disappeared, but they never completed it. Professor Shulough later fell into that same pit while being stalked by a Witiku. Rose threw a vine down the pit, told the Professor to climb, and tackled the Witiku, which fell into the pit and was trapped. (PROSE: The Price of Paradise)
