Sontaran breeding planet
From Tardis Wiki, the free Doctor Who reference
The Sontaran Breeding Planet is the planet where the Sontarans cloned themselfs to form massive armys. The Sontarans invaded Earth beacuse they said their breeding planet was missing so they polluted the earth with clone feed to make earth their new breeding planet. The Sontaran Breeding Planet was one of the 27 planets stolen by Davros. (DW: The Stolen Earth)