 Two years later American artist David Ellis produced a deck of 99 cards with abstract paintings called ecco.The Canadian naturalist and artist [Christian Gronau] focused on our interaction with the natural environment with a deck of 88 cards called Habitat (1993).Ely Raman explored a different use of two–deck interactivity with a pair of decks called Persona (1994), one of portraits; the other of abstract designs that can symbolize possible social interactions or personal relationships.