Great Power

The Great Power was an Earth mushroom known to the Voords. It grew in a South American jungle, could bestow superhuman powers, and was used by Inca priests. When the Daleks learned of it, they pretended to form an alliance with the Voords in order to acquire it and use it to increase their brain power. After they destroyed the Voords, the Chief Voord led the Daleks to the mushroom, knowing that was poisonous to them. Although the Great Power did indeed increase their brain power, allowing them to shoot down a fleet of Earth fighters, they all died shortly afterwards. (PROSE: Doctor Who and the Daleks)