LEGO Slizer, which was also known as Throwbots in the US and Canada, was a subtheme of TECHNIC that launched in 1999 and replaced by Robo Riders in 2000. The Slizer sets came with two discs that can be thrown using a special flinger arm.
2000 LEGO Sets
The turn of the millennium was an important year for LEGO. Not only did LEGO produce some investible sets for 2000, we saw some transition in the company. First, set designer and the inventor of the minifigure, Jens Nygaard Knudsen, retired from The LEGO Group. Second, The British Association of Toy Retailers name the LEGO brick "Toy of the Century". With 2000 LEGO released just a couple of new themes including TECHNIC Roboriders and Race. The Rock Raiders, Nijna and the Slizer/Throwbots themes were discontinued.