Galidor is a 2002 theme released by LEGO based on a TV show. The theme is best known for not selling any sets.
The plot of Galidor was about... ...you know, even us at Bloxopedia don't know what it was about! Just go watch the crappy show yourself.
The idea of the theme was to swap characters limbs, to give them new powers. The problem with this was that the figures looked less like LEGO and more like cheap action figures that break as soon as you open them. To get people to like the concept, they made promotional sets that look even less like LEGO.
The theme was so popular that 99.8% of the sets ended up in the bargain bin at Toys R Us, alongside other top-selling products such as Barbie Horse Adventures.