The Blockocactus mcshittius is a reverent and reoccurring species of cactus on the interwebs and other domains of existence. They're defined by their green colour and a defined, rigid shape. Blockocactus only exist in the future, as any Blockocactus that exists in the present is automatically burnt up by the time Joker's imaginary friend. Any Blockocactus caught in the past or present are to be sent straight to officers of the law. These officers of the law may or may not be from space.