Nepenthes rajah x peltata is an incredible cross between 2 giant species. The grex was given the unofficial name x Leviathan when it was first made as a collaboration between Jeremiah Harris and Shinya Yamada of Japan. Its features are so desirable that one plant set the Guinness World Record for most expensive carnivorous plant sale.
Plants for sale here are much more readily available. They were produced by Borneo Exotics as a cross between a Kew Gardens rajah and seed grown peltata with a rich, red appearance. Plants for sale are from a random assortment of clones, BE-4510.