Lurbos 3 was a tropical rainforest world.
When the Tenth Doctor, Heather McCrimmon and Wolfgang Ryter visited the planet, they were horrified to discover that the population of the world had been forced into a lifelong sleep by a Dream Sucker. After Heather was forced into an endless dream herself, the Doctor allowed the Dream Sucker to send him to sleep and brought up his darkest memories, which the Dream Sucker couldn't bear to see. Weakened, the Dream Sucker awoke the population and Heather. (COMIC: Sweet Dreams)