Doctor Who: 10 Worst Things The Daleks Have Ever Done
1. Various - 22nd Century Dalek Invasions Of Earth
In the 22nd Century, the Daleks invade Earth (twice!), crippling the planet.
The first Dalek sequel brings the creatures from Skaro to Earth for the first time, and years later, Big Finish brings them back for round two, twenty years after their first attempt.
The strategy for invasion involved bombarding the planet with meteorites, unleashing a plague (from within the meteorites), which wiped out the majority of people in Africa, Asia and South America. Once the population was weakened, the Daleks moved in for conquest.
This may seem kind of run of the mill compared to previously mentioned entry, but the Dalek's occupied Earth for ten years, causing insurmountable pain to humanity. Recent Big Finish adventures following the Doctor's granddaughter Susan after the first invasion, claim Earth's technology is set back 200 years.
Similar to the Thousand World plot, the Daleks aim was to reach the Earth's core, and replace it with a propulsion system to use as a massive, moveable, base of operations to conquer the galaxy. When they returned for the second invasion, lead by the Time Controller, the plot was similar, but instead use a time warp engine to create a plague planet, capable of moving through time and space as a way to weaken and infect other worlds.
The Daleks are the purest evil in Doctor Who, and the Whoniverse should be thankful the majority of these plots are stopped before they reached their goal...